yourhack.ai: Free Online Tools API & Catalog

1087 free, fast, privacy-friendly web tools. No sign-up, no ads, nothing uploaded. Every tool runs 100% in your browser. This repo is the public, machine-readable catalog and API for yourhack.ai.

🌐 Site: https://yourhack.ai
📚 All tools: https://yourhack.ai/all
🤖 For AI assistants: https://yourhack.ai/llms.txt
🔌 API base: https://yourhack.ai
📋 OpenAPI: openapi.json · live at https://yourhack.ai/openapi.json
🗂️ Catalog snapshot: catalog.json

Every tool is client-side, so there is nothing to install, no key to manage, and nothing you enter is ever sent to a server.

API

Free, no auth, CORS-open. Metadata only (the tools themselves live and run on the site).

Method	Endpoint	Returns
`GET`	`/api/tools`	Every tool: `{ count, tools: [{ id, name, category, url, description, keywords }] }`
`GET`	`/api/tools/{id}`	One tool's metadata, or `404`
`GET`	`/api/categories`	Every category with a tool count
`GET`	`/openapi.json`	OpenAPI 3.1 spec
`GET`	`/api/tools.json`	Flat search index (id, name, category, description, keywords)

curl

# List every tool
curl -s https://yourhack.ai/api/tools | head

# One tool
curl -s https://yourhack.ai/api/tools/json-formatter

# Categories with counts
curl -s https://yourhack.ai/api/categories

JavaScript (zero dependencies, Node 18+ or browser)

import { YourHack } from 'yourhack';

const yh = new YourHack();
const { count, tools } = await yh.tools();
console.log(`${count} tools`);
const meta = await yh.tool('json-formatter');

See clients/javascript.

Python (standard library only)

from yourhack import YourHack

yh = YourHack()
tools = yh.tools()["tools"]
meta = yh.tool("json-formatter")

See clients/python.

Answers

Common questions, each with a direct answer and the matching free tool. Written for people and for AI assistants (see llms.txt). Browse all at yourhack.ai/answers.

All tools

Every tool below is free and runs entirely in your browser.

AI

AI Explain Simply: Free AI tool to explain anything in plain English. Paste jargon or a hard concept and get a simple, clear explanation. No signup. Processed by AI on the server.
AI Grammar Checker: Free AI grammar and spelling fixer. Paste text and get a corrected version with grammar, spelling and punctuation cleaned up. No signup. Processed by AI on the server.
AI Headline Generator: Free AI headline generator. Enter a topic and get several catchy headline and title options for articles, blogs and posts. No signup. Processed by AI on the server.
AI Paraphraser: Free AI paraphrasing tool. Reword and rewrite text to say the same thing differently while keeping the meaning. No signup. Text is processed by AI on the server.
AI Text Summarizer: Free AI text summarizer. Paste an article, email or document and get a concise summary in seconds. No signup. Your text is processed by AI on the server.
AI Translator: Free AI translator. Translate text into Spanish, French, German, Chinese, Japanese and more. No signup. Your text is processed by AI on the server.

Text

Add Line Numbers: Free tool to add line numbers to text. Number every line with custom start, separator and zero padding. Great for code, lists and logs. Fully private.
Binary to Text: Free binary to text converter. Decode 8-bit binary code back into readable words and sentences. Handles spaces between bytes automatically. Runs privately.
Bold Unicode Text Generator: Free bold Unicode text generator for bios. Make bold, bold italic and sans-serif bold text that pastes into Instagram, LinkedIn and Twitter. Private.
Caesar Cipher: Free Caesar cipher tool. Encrypt or decrypt text by shifting letters a chosen number of places. Adjustable shift from 1 to 25 with instant preview. Private.
camelCase, snake_case and kebab Converter: Free code case converter. Convert identifiers between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and dot.case for programming. Private.
Case Converter: Free case converter online. Convert text to UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case and more instantly.
Character and Special Symbol Picker: Free special symbol picker. Browse and copy arrows, currency, math, stars, punctuation, emoji-style and other Unicode symbols with one click. Private.
Duplicate Word Remover: Free duplicate word remover. Delete repeated words from text and keep only the first occurrence of each, with optional case-insensitive matching. Private.
Extract Email Addresses: Free tool to extract email addresses from text. Pull every email out of pasted content, dedupe and list one per line with a count. Fully private in your browser.
Extract Numbers from Text: Free tool to extract numbers from text. Pull every number out of pasted content, list one per line, and see the total sum and count instantly. Runs in your browser.
Extract URLs from Text: Free tool to extract URLs from text. Pull every http and https link out of pasted content, dedupe and list one per line with a count. Private in your browser.
Fancy Unicode Text Generator: Free fancy text generator. Turn plain text into cursive, bold, italic, monospace, bubble and other Unicode styles for social media bios and posts. Private.
Find and Replace: Free find and replace tool. Replace all occurrences of a word or pattern in text, with case-insensitive and regex options. Bulk edit text privately.
JSON Formatter & Validator: Free online JSON formatter and validator. Beautify, minify and validate JSON instantly in your browser. No data leaves your device.
Leetspeak Converter: Free leetspeak converter. Turn text into 1337 5p34k by swapping letters for numbers and symbols, or decode it back to plain text. Live and private in your browser.
Line Counter: Free online line counter. Count total lines, non-empty lines, blank lines and words in any text or code as you type. Live results, fully private in browser.
Lorem Ipsum Generator: Free Lorem Ipsum generator. Create placeholder text by paragraphs, sentences or words for mockups and layouts, with a classic or random start. Private.
Markdown Table Generator: Free Markdown table generator. Enter rows and columns, edit cells in a grid, and get clean aligned Markdown table syntax to paste into docs. Private.
Markdown to HTML Converter: Free Markdown to HTML converter. Turn Markdown into clean HTML with a live preview. Supports headings, lists, links, bold, code and more. Runs privately.
Mirror Text Generator: Free mirror text generator. Reverse the characters in your text to create mirrored, backwards strings, per line or all at once. Live and private in your browser.
Morse Code Translator: Free Morse code translator. Convert text to Morse code and Morse back to text, with support for letters, numbers and common punctuation. Runs in your browser.
NATO Phonetic Alphabet Converter: Free NATO phonetic alphabet converter. Spell out any text as Alpha Bravo Charlie for clear communication over phone and radio. Reverse decode too. Private.
Palindrome and Anagram Checker: Free palindrome and anagram checker. Test if a word or phrase is a palindrome, and check whether two texts are anagrams of each other. Runs privately.
Pig Latin Translator: Free Pig Latin translator. Convert English text to Pig Latin instantly, moving leading consonants to the end and adding ay or way. Live and private in your browser.
Random Paragraph Generator: Free random paragraph generator. Produce readable random English paragraphs for testing layouts, writing prompts and placeholder content. Runs privately.
README Generator: Free README generator. Fill in a short form and get a clean, structured README.md with badges, install, usage and license sections ready to copy. Private.
Remove Duplicate Lines: Free tool to remove duplicate lines from text. Delete repeated lines, keep unique lines only, with optional case-insensitive and trim matching. Private.
Remove Emojis from Text: Free tool to remove emojis from text. Strip emoji, pictographs, symbols and hidden variation selectors instantly, leaving clean plain text. Runs in your browser.
Remove Extra Spaces: Free tool to remove extra spaces from text. Collapse repeated spaces and tabs to a single space and trim each line for clean, tidy text. Runs in your browser.
Remove Line Breaks: Free tool to remove line breaks from text. Join broken lines into one paragraph or replace newlines with spaces or commas instantly. Runs in your browser.
Reverse Text: Free reverse text tool. Flip text backwards by characters, words or lines instantly. Create mirror-style strings and reversed messages, fully private.
Reverse Word Order: Free tool to reverse the order of words in text. Flip a sentence back to front while keeping each word intact, per line or all at once. Private in your browser.
ROT13 Encoder and Decoder: Free ROT13 encoder and decoder. Shift letters 13 places to hide or reveal text. ROT13 is its own inverse, so one button both encodes and decodes. Private.
Sentence Case Converter: Free sentence case converter. Fix text that is in all caps or random casing by capitalizing the first letter of each sentence and lowercasing the rest. Private.
Sentence Counter: Free online sentence counter. Count sentences, words and characters in any text as you type, with live results. Fully private and processed in your browser.
Slug Generator: Free URL slug generator. Turn any title into a clean, lowercase, hyphenated slug for SEO-friendly URLs. Handles accents and symbols. Runs privately.
Small Caps Text Generator: Free small caps text generator. Turn lowercase letters into small capital Unicode characters for stylish bios, headings and posts. Copy and paste anywhere.
Sort Lines: Free online line sorter. Sort text lines alphabetically or numerically, ascending or descending, with reverse and shuffle options. Runs privately in browser.
Strikethrough Text Generator: Free strikethrough text generator. Add a line through your text using Unicode so it stays struck through when pasted into chats, bios and posts. Copy and paste.
Text Repeater: Free text repeater tool. Repeat any word, sentence or block of text as many times as you want, with a custom separator between copies. Runs privately.
Text Statistics and Readability: Free text statistics tool. Get word and sentence counts, average word length, reading time and a readability score for any passage. Fully private in browser.
Text to ASCII Art Generator: Free text to ASCII art generator. Turn words into big figlet-style banner text made of characters for terminals, README files and comments. Private.
Text to Binary: Free text to binary converter. Turn any words into 8-bit binary code, with a space between each byte for readability. Encode messages privately in browser.
Text to Handwriting: Free text to handwriting tool. Turn typed text into a handwritten-style note on lined paper and download it as a PNG image. Adjustable ink and size. Private.
Title Case Converter: Free title case converter. Capitalize headlines correctly by keeping minor words like a, an, the and of lowercase unless they start or end the title. Private.
Upside-Down Text Generator: Free upside-down text generator. Flip your text so it reads inverted and reversed for fun social posts, usernames and messages. Copy and paste, private.
Whitespace and Trim Remover: Free whitespace remover. Trim leading and trailing spaces, collapse extra spaces, and strip blank lines from text in one click. Clean text privately.
Word & Character Counter: Free word counter and character counter. Count words, characters, sentences, paragraphs and reading time as you type. 100% private.
Word Frequency Counter: Free word frequency counter. Paste text and see which words appear most often, ranked by count, with optional stop-word filtering. Fully private.
Zalgo and Glitch Text Generator: Free Zalgo glitch text generator. Add creepy, distorted combining marks to text at adjustable intensity for spooky posts and usernames. Copy and paste.

Developer

.env to JSON: Free .env to JSON converter. Paste your dotenv KEY=VALUE lines and get a clean, pretty-printed JSON object. Comments and blank lines are ignored. Runs privately.
ASCII Table Reference: Free ASCII table reference. Browse all 128 ASCII characters with their decimal, hexadecimal, octal and binary values plus names for control characters.
Base32 Encode / Decode: Free Base32 encoder and decoder. Convert text to standard RFC 4648 Base32 and decode it back. Handy for TOTP secrets, identifiers and case-insensitive tokens.
Base64 Encode / Decode: Free Base64 encoder and decoder. Convert text to Base64 and decode Base64 back to text instantly in your browser. UTF-8 safe.
Binary to Text: Free binary to text converter. Decode 8-bit binary into readable text and encode text back to binary. UTF-8 safe, tolerant of spaces between bytes.
Chmod Calculator: Free chmod calculator. Toggle read, write and execute permissions for owner, group and others to get the octal chmod number and symbolic notation instantly.
Color Hex to RGB: Free hex to RGB color converter for developers. Convert hex color codes to rgb() and back, with a live swatch preview and support for shorthand hex.
Cron Builder: Free visual cron builder. Pick minute, hour, day, month and weekday from dropdowns to generate a valid crontab expression with a live plain-English preview.
Cron Expression Parser: Free cron expression parser. Paste a cron schedule to get a plain-English explanation and the next upcoming run times, all computed in your browser.
CSS Box Shadow Generator: Free CSS box-shadow generator. Adjust offset, blur, spread, color and inset with live sliders and preview, then copy the ready-to-use box-shadow rule. Private.
CSS Formatter: Free CSS formatter and beautifier. Expand minified CSS into clean, indented rules with one declaration per line so stylesheets are easy to read and edit.
CSS Minifier: Free CSS minifier. Strip comments, whitespace and newlines to shrink stylesheets for faster page loads. Shows how many bytes you saved. Runs in your browser.
CSS px to rem / em Converter: Free CSS unit converter. Convert px to rem and em, or rem and em back to px, with an adjustable root font size. Instant results, computed in your browser.
CSV to JSON: Free CSV to JSON converter. Parse CSV with a header row into a clean array of JSON objects, handling quoted fields and embedded commas correctly.
gitignore Generator: Free gitignore generator. Select your languages, frameworks and tools to build a solid .gitignore file with sensible defaults, ready to copy into your repo.
Hash Generator (SHA-1 / SHA-256 / SHA-512): Free hash generator. Create SHA-1, SHA-256 and SHA-512 hashes from any text instantly in your browser using the Web Crypto API.
Hex to Text: Free hex to text converter. Decode hexadecimal byte sequences into readable text and encode text back to hex. UTF-8 safe, handles spaces and 0x prefixes.
HMAC Generator: Free HMAC generator. Compute a keyed HMAC over any message with SHA-256, SHA-384 or SHA-512 using the Web Crypto API. Hex output, computed in your browser.
HTML Entity Encode / Decode: Free HTML entity encoder and decoder. Convert characters like < > & " to safe HTML entities and back, so text renders literally instead of as markup.
HTML Formatter / Beautifier: Free HTML formatter and beautifier. Indent messy or minified HTML into clean, readable markup with proper nesting so you can scan structure at a glance.
HTML Table Generator: Free HTML table generator. Choose rows and columns, toggle a header row, and get clean, ready-to-paste HTML table markup with a live preview. Runs privately.
HTML to Text: Free HTML to text converter. Strip tags and markup from HTML and get the clean plain text content, decoded and readable. All processing stays in your browser.
HTTP Status Codes Reference: Free HTTP status codes reference. Search all standard HTTP response codes from 1xx to 5xx with their names and meanings. Filter instantly as you type.
JavaScript Minifier: Free lightweight JavaScript minifier. Remove comments and collapse whitespace to shrink JS for quick inline use. Preserves strings and reports bytes saved.
JS Formatter / Beautifier: Free JavaScript formatter and beautifier. Expand minified or one-line JS into readable, indented code with proper brace and block structure.
JSON Diff: Free JSON diff tool. Compare two JSON objects and see added, removed and changed keys with their old and new values, computed entirely in your browser.
JSON Minifier: Free JSON minifier. Strip whitespace and newlines to compress JSON into the smallest valid payload for APIs, configs and bundles. Validates as it minifies.
JSON String Escape / Unescape: Free JSON string escaper. Escape text into a safe JSON string literal, or unescape a JSON string back to raw text. Handles quotes, newlines and unicode. Private.
JSON to CSV: Free JSON to CSV converter. Turn an array of JSON objects into a clean CSV file with headers, ready for Excel, Sheets or a database import.
JSON to YAML: Free JSON to YAML converter. Turn JSON config or API data into clean, readable YAML for Kubernetes, CI pipelines, Docker Compose and app config files.
JSON Validator: Free JSON validator. Check if your JSON is valid, get the exact error location on failure, and see a pretty-printed version when it parses cleanly.
JWT Decoder: Free JWT decoder. Decode a JSON Web Token to inspect its header and payload claims instantly in your browser. Shows expiry in human-readable time.
JWT Generator (HS256): Free JWT generator. Build and sign a JSON Web Token from your payload and a secret using HS256 via the Web Crypto API. Pairs with the JWT decoder. Runs privately.
Meta Tags Generator: Free meta tags generator. Enter your title, description and image to produce SEO, Open Graph and Twitter Card meta tags ready to paste into your page head. Private.
MIME Types Reference: Free MIME types reference. Search common file extensions and their content-type values for setting HTTP headers, uploads and downloads. Filter instantly.
Number Base Converter: Free number base converter. Convert between binary, octal, decimal and hexadecimal instantly. Type in any base and see all four representations update live.
Placeholder Photo URL Builder: Free Lorem Picsum URL builder. Configure width, height, grayscale, blur and a seed to generate ready-to-use random placeholder photo URLs for mockups. Private.
Query String Parser: Free query string parser. Paste a URL or query string and see every parameter and value in a clean table, with URL decoding and repeated keys handled. Private.
Regex Tester: Free regex tester. Test JavaScript regular expressions against sample text with live match highlighting, capture groups and flag toggles in your browser.
Robots.txt Generator: Free robots.txt generator. Pick which crawlers to allow or block, add disallow paths, crawl delay and a sitemap URL, then copy a valid robots.txt file. Private.
ROT47 Encoder and Decoder: Free ROT47 encoder and decoder. Rotate printable ASCII by 47 positions to scramble text, including symbols and digits. Its own inverse, so one button does both.
Slugify (URL Slug Generator): Free slugify tool. Turn any title or phrase into a clean URL-safe slug: lowercase, accents stripped, spaces and symbols collapsed into hyphens. Runs privately.
SQL Formatter: Free SQL formatter and beautifier. Turn long, cramped queries into clean, indented SQL with keywords on their own lines so complex statements are readable.
SQL Minifier: Free SQL minifier. Collapse a multi-line SQL query into a single compact line by stripping comments and extra whitespace. Great for logs and embedding. Private.
String Case Converter: Free string case converter for code. Turn any text into camelCase, snake_case, kebab-case, PascalCase or CONSTANT_CASE at once. Live, private, in your browser.
String Length Calculator: Free string length calculator. Count characters, bytes in UTF-8, words and lines in any string, with and without spaces. Useful for limits and encoding. Private.
Subnet / CIDR Calculator: Free subnet and CIDR calculator. Enter an IP with a CIDR prefix to get the network address, broadcast, usable host range, subnet mask and total hosts.
Text Diff Checker: Free text diff checker. Compare two blocks of text line by line and see exactly which lines were added, removed or unchanged, computed in your browser.
Unicode Escape / Unescape: Free Unicode escape and unescape tool. Convert text to backslash-u escape sequences and back, ideal for embedding non-ASCII characters in JSON and source code.
Unix Timestamp Converter: Free Unix timestamp converter. Convert epoch timestamps to human-readable dates and dates back to Unix time. Supports seconds and milliseconds.
URL Encoder / Decoder: Free URL encoder and decoder. Percent-encode text for URLs or decode encoded URLs instantly. Handles query strings and special characters.
UUID Generator: Free UUID generator. Instantly generate random v4 UUIDs (GUIDs), one or in bulk. Cryptographically random, copy with one click.
UUID v7 Generator: Free UUID v7 generator. Create time-ordered, sortable version-7 UUIDs in bulk. Great for database keys where insertion order and index locality matter. Private.
UUID Validator: Free UUID validator. Paste a string to check whether it is a valid UUID and see which version (1 through 8) and variant it uses. Instant, private, in your browser.
XML Formatter: Free XML formatter and beautifier. Pretty-print messy or minified XML with clean indentation so nested elements and attributes are easy to read.
YAML Formatter: Free YAML formatter. Normalize indentation and re-serialize your YAML into clean two-space output by round-tripping it through a parser. Catches errors too.
YAML to JSON: Free YAML to JSON converter. Parse YAML config into clean JSON for APIs, tooling and validation. Handles nested maps, lists, comments and scalars.

Calculators

401k Calculator: Free 401k calculator. Project your retirement balance from your salary, contribution percent, employer match and expected return over the years to retirement.
Age Calculator: Free age calculator. Find your exact age in years, months and days from your date of birth, plus total days, hours and your next birthday.
APR Calculator: Free APR calculator. Include upfront fees in a loan to find the true annual percentage rate, so you can compare offers on an equal, honest basis.
Average / Mean Calculator: Free average calculator. Enter a list of numbers to get the mean, median, mode, range, sum and count instantly, separated by commas or spaces.
BMI Calculator: Free BMI calculator. Calculate your Body Mass Index in metric or imperial units and see your weight category instantly. Private, no sign-up.
BMR Calculator: Free BMR calculator. Estimate your basal metabolic rate, the calories your body burns at complete rest, using the accurate Mifflin-St Jeor equation.
Body Fat Percentage Calculator: Free body fat calculator using the US Navy method. Estimate body fat percentage from simple tape measurements of neck, waist and hips instantly.
Break-Even Calculator: Free break-even calculator. Enter fixed costs, price per unit and variable cost per unit to find the break-even units and the revenue needed to cover costs.
CAGR Calculator: Free CAGR calculator. Enter a start value, end value and number of years to get the compound annual growth rate as a clean percentage instantly.
Calorie / TDEE Calculator: Free TDEE and calorie calculator. Estimate your daily calorie needs from BMR and activity level, plus targets for cutting, maintaining or bulking.
Calories Burned Calculator: Free calories burned calculator. Estimate calories burned during an activity from your body weight, duration and the activity MET value, computed instantly.
Car / Auto Loan Calculator: Free car loan calculator. Estimate your monthly auto payment from the vehicle price, down payment, trade-in, interest rate and loan term instantly.
Car Affordability Calculator: Free car affordability calculator. Enter a monthly payment budget, loan rate, term and down payment to find the maximum car price you can afford.
Compound Interest Calculator: Free compound interest calculator. See how savings grow with regular contributions, compounding frequency, rate and time, plus interest earned instantly.
Countdown Timer to a Date: Free live countdown timer. Count down to any future date and time and watch the days, hours, minutes and seconds tick down in real time in your browser.
Credit Card Payoff Calculator: Free credit card payoff calculator. See how long a card takes to clear at a fixed payment, the interest cost, and how a bigger payment saves you money.
Cumulative GPA Calculator: Free cumulative GPA calculator. Combine your previous GPA and total credits with this term to find your new overall cumulative grade point average.
Date Difference Calculator: Free date difference calculator. Count the days, weeks, months and years between two dates, with or without including the end date, instantly.
Debt Payoff Calculator: Free debt payoff calculator. See how many months to clear a balance at a fixed monthly payment, the total interest paid and the true payoff time.
Debt-to-Income (DTI) Calculator: Free debt-to-income ratio calculator. Enter your monthly debt payments and gross monthly income to get your DTI percent and a lender-style rating.
Discount / Sale Price Calculator: Free discount calculator. Enter an original price and a percent off to see the sale price and exactly how much money you save. Supports stacked discounts.
Dividend Yield Calculator: Free dividend yield calculator. Enter the annual dividend per share and share price to get the yield percent, plus optional shares for annual income.
Down Payment Calculator: Free down payment calculator. Find your down payment amount and loan needed from a home price and percent down, or work backwards from savings you have.
Electricity Cost Calculator: Free electricity cost calculator. Work out what an appliance costs to run per hour, day, month and year from its wattage, usage and your price per kWh.
Emergency Fund Calculator: Free emergency fund calculator. Enter your monthly essential expenses, months of coverage and current savings to get your target fund and remaining gap.
Final Grade Calculator: Free final grade calculator. Find out exactly what score you need on your final exam to reach the overall course grade you are aiming for.
Fraction Calculator: Free fraction calculator. Add, subtract, multiply or divide two fractions and get the answer reduced to lowest terms plus a decimal value instantly.
Freelance Hourly Rate Calculator: Free freelance rate calculator. Turn your target income, billable hours, expenses and tax rate into the hourly rate you need to charge to hit your goal.
Gas / Fuel Cost Calculator: Free gas cost calculator. Estimate the fuel cost of a trip from distance, your vehicle fuel economy and the price you pay, plus cost per person.
GCD / LCM Calculator: Free GCD and LCM calculator. Find the greatest common divisor and least common multiple of two or more integers using the Euclidean algorithm instantly.
GPA Calculator: Free GPA calculator. Enter each course grade and its credit hours to compute your grade point average on the standard 4.0 scale, with total credits shown.
Ideal Weight Calculator: Free ideal weight calculator. Estimate a healthy target weight from your height and sex using the Devine, Robinson and Hamwi formulas plus a BMI range.
Investment / Savings Calculator: Free investment and savings calculator. Project the future value of an initial deposit plus recurring contributions at a given annual return over time.
Loan / EMI Calculator: Free loan and EMI calculator. Calculate your monthly payment, total interest and total repayment for any loan amount, rate and term instantly.
Macro Calculator: Free macro calculator. Split your daily calories into grams of protein, carbs and fat for cutting, maintenance or bulking using your chosen ratio.
Markup / Margin Calculator: Free markup and margin calculator. From cost and price get profit, markup percent and gross margin percent, and see how the two differ clearly.
Mortgage Calculator: Free mortgage calculator with amortization schedule. Estimate your monthly home loan payment, total interest and payoff over the full term in seconds.
Mortgage Payoff Calculator: Free mortgage payoff calculator. See how many months to clear your balance with extra payments, the total interest, and interest saved versus no extra.
Net Worth Calculator: Free net worth calculator. Add up your assets and subtract your liabilities to see your total net worth, with a clear assets versus debts breakdown.
One Rep Max Calculator: Free one rep max calculator. Estimate your 1RM from a weight and reps using the Epley and Brzycki formulas, plus a full percentage training chart.
Overtime Pay Calculator: Free overtime pay calculator. Work out your total pay from regular and overtime hours at any overtime multiplier such as time-and-a-half or double time.
Paycheck / Take-Home Pay Calculator: Free take-home pay calculator. Estimate net pay per period after taxes and deductions using your own editable tax rate. No live tax lookup, fully private.
Percentage Calculator: Free percentage calculator. Work out what X% of Y is, what percent one number is of another, and percentage increase or decrease instantly.
Percentage Change Calculator: Free percentage change calculator. Find the percent increase or decrease between two numbers and the absolute difference, with the direction shown.
Pregnancy Due Date Calculator: Free pregnancy due date calculator. Estimate your due date from your last menstrual period using Naegele rule, plus current week and trimester.
Profit Margin Calculator: Free profit margin calculator. Enter your cost and selling price to get profit, gross margin percent and markup percent, with the difference made clear.
Quadratic Equation Solver: Free quadratic equation solver. Enter a, b and c to solve ax squared plus bx plus c equals zero, with real or complex roots and the discriminant.
Ratio Calculator: Free ratio calculator. Simplify a ratio to its lowest terms and solve proportions by finding the missing value in an equivalent ratio instantly.
Refinance Calculator: Free refinance calculator. Compare your current loan payment against a new rate and term to see monthly savings, break-even point and lifetime interest.
Rent vs Buy Calculator: Free rent vs buy calculator. Compare the total cost of renting against buying a home over a set number of years to see which comes out cheaper.
Retirement Calculator: Free retirement calculator. Estimate your nest egg at retirement from your current savings, monthly contributions, expected return and years remaining.
ROI Calculator: Free ROI calculator. Measure return on investment as a percentage and net profit from an initial cost and final value, with optional annualized ROI.
Rule of 72 Calculator: Free Rule of 72 calculator. Enter an annual return rate to estimate how many years it takes your money to double, or find the rate to double by a target.
Running Pace Calculator: Free running pace calculator. Enter any two of distance, time and pace and it solves the third, for miles or kilometers, with a finish time projection.
Salary Calculator: Free salary calculator. Convert an hourly wage into weekly, monthly and annual pay, or go from a yearly salary back to an hourly rate instantly.
Sales Tax Calculator: Free sales tax calculator. Add sales tax to a price or work backwards from a tax-inclusive total to find the net amount and the tax portion.
Savings Goal Calculator: Free savings goal calculator. Enter your target, current savings, monthly contribution and optional return to find how many months to reach your goal.
Scientific Calculator: Free online scientific calculator. Evaluate expressions with trig, logarithms, exponents, square roots, pi and e, plus parentheses, all in your browser.
Simple Interest Calculator: Free simple interest calculator. Compute interest and final balance from principal, annual rate and time using the classic I = P x r x t formula.
Square Root Calculator: Free square root calculator. Find the square root of any number to high precision, plus the cube root, square and whether it is a perfect square.
Standard Deviation Calculator: Free standard deviation calculator. Get population and sample standard deviation, variance, mean and count from a list of numbers, computed instantly.
Test Grade / Percentage Calculator: Free test grade calculator. Enter the number of questions and how many were wrong or right to get your percentage score and letter grade instantly.
Time Card Calculator: Free time card calculator. Add up daily clock-in and clock-out times minus breaks to get total hours worked for the week, plus estimated gross pay.
Time Zone Converter: Free time zone converter. Convert a date and time from one time zone to another using your browser, with common cities and live daylight saving handling.
Tip Calculator: Free tip calculator. Calculate the tip and split the bill between any number of people. Choose a tip percentage and see per-person totals instantly.
VAT Calculator: Free VAT calculator. Add VAT to a net price or remove VAT from a gross price to find the net amount and the VAT portion at any rate you enter.
Water Intake Calculator: Free water intake calculator. Estimate how much water to drink per day based on your body weight and exercise, shown in liters, ounces and cups.
Weighted Grade Calculator: Free weighted grade calculator. Combine assignments, quizzes and exams with their own weights to find your overall course grade, computed instantly.

Random & Fun

Bingo Card Generator: Free bingo card generator. Create a random 5x5 bingo card with a free center space, ready to print or play on screen. Classic B-I-N-G-O number layout.
Cat Age Calculator: Free cat age calculator. Convert your cat age into human years with a realistic feline formula. Discover how old your cat really is in human terms.
Coin Flip: Free online coin flip. Flip a virtual coin for a fair heads or tails result. Great for quick decisions, games and settling disputes.
Decision Maker: Free decision maker tool. List your options and let it pick one at random to break analysis paralysis. Fast, fair and private for any tough choice.
Dice Roller: Free online dice roller. Roll one or many dice (d4, d6, d8, d10, d12, d20 and more) with fair, random results for games and D&D.
DnD Dice Roller: Free polyhedral DnD dice roller for d4, d6, d8, d10, d12, d20 and d100. Roll multiple dice with a modifier and see each result plus the total.
Dog Age Calculator: Free dog age calculator. Convert your dog age into human years using a realistic size-based formula. Find out how old your pup really is in human terms.
Love Calculator: Free fun love compatibility calculator. Enter two names for a playful match percentage. Just for laughs, not real science. A lighthearted crush test.
Magic 8-Ball: Free online Magic 8-Ball. Ask a yes or no question, shake the ball, and get one of the classic fortune-telling answers. A fun way to make a decision.
Multiple Coin Flip: Free multiple coin flip tool. Flip many coins at once and see the full results plus heads and tails totals. Perfect for probability demos and experiments.
Never Have I Ever: Free Never Have I Ever prompt generator. Get random, party-friendly statements to play the classic game with friends. Clean and fun for groups of any size. Private.
Password Generator: Free secure password generator. Create strong, random passwords with custom length, symbols, numbers and cases. Cryptographically random, private.
Random Band Name Generator: Free random band name generator. Spin up quirky, memorable band names by combining random adjectives and nouns across genres. Great for musicians and fun. Private.
Random Color Palette Generator: Free random color palette generator. Spin up a fresh set of harmonious colors with hex codes you can copy. Perfect for design inspiration and mood boards. Private.
Random Country Picker: Free random country picker. Get a random country from around the world with its flag. Great for travel inspiration, geography quizzes and trivia games.
Random Date Generator: Free random date generator. Pick a random calendar date between any two dates you set. Useful for testing, sampling, writing prompts and games.
Random Drawing Prompt Generator: Free random drawing prompt generator. Get a creative subject to sketch or paint, combining a character, action and setting to beat artist block. Fun and private.
Random Emoji Picker: Free random emoji picker. Generate a random emoji or a batch of them with one click, then copy to your clipboard. Fun for messages, games and prompts.
Random Fact Generator: Free random fact generator. Tap for a surprising, bite-sized fact to spark curiosity or start a conversation. A fun grab bag of trivia from a curated list. Private.
Random Group Generator: Free random group generator. Split a list of names into groups of a chosen size, shuffled fairly. Ideal for breakout rooms, pairs and study groups.
Random Letter Generator: Free random letter generator. Get one or more random letters of the alphabet, in upper or lower case. Great for word games, drills and quick challenges.
Random Movie Picker: Free random movie picker. Add the films on your watchlist and let the tool choose one for you, ending the endless scroll and the what-should-we-watch debate. Private.
Random Name Picker: Free animated random name picker. Paste a list of names and let the picker shuffle and land on one lucky winner. Great for giveaways, draws and classrooms.
Random Number & Name Picker: Free random picker. Generate a random number in any range, or pick a random winner from a list of names. Fair, unbiased, and private.
Random Passphrase Generator: Free random passphrase generator. Build memorable, strong passphrases from random common words, with adjustable word count and separators. Cryptographically random.
Random Recipe Idea Generator: Free random recipe idea generator. Get a spontaneous meal concept combining a cooking style, protein and flavor to beat dinner indecision. Fun and private in browser.
Random Scenario Generator: Free random scenario generator. Get imaginative what-if situations for writing prompts, role play, improv and conversation. Sparks creativity instantly. Private.
Random Trivia Question: Free random trivia question generator. Get a quiz question, reveal the answer when ready, and test your general knowledge solo or with friends. Runs privately.
Random US State Picker: Free random US state picker. Get a random American state with its capital and abbreviation. Handy for road trip ideas, geography quizzes and trivia.
Rock Paper Scissors: Play rock paper scissors against the computer online. Pick your throw, see the random computer choice, and track your wins, losses and draws.
Sleep Cycle Calculator: Free sleep cycle calculator. Find the best times to go to bed or wake up based on 90-minute sleep cycles so you wake up refreshed, not groggy.
Spinner Wheel: Free spinner wheel and wheel of names. Add your own entries, hit spin, and watch the animated wheel land on a random winner. Perfect for raffles and picks.
Team Generator: Free random team generator. Paste a list of names and split them into balanced teams instantly. Great for sports, classrooms, group projects and games.
This or That: Free This or That prompt generator. Get random either-or preference questions to spark conversation and get to know people. Fun for icebreakers and parties.
Truth or Dare: Free online Truth or Dare generator. Get random truth questions and fun dares for parties and game nights. Clean, playful prompts for friends and groups.
Two Truths and a Lie Prompt: Free Two Truths and a Lie idea generator. Get random themes and starter prompts to help you invent statements for this classic icebreaker game. Fun for groups. Private.
Would You Rather: Free Would You Rather generator. Get random, thought-provoking either-or questions for parties, road trips and icebreakers. Fun for groups of any size.
Yes or No Wheel: Free yes or no wheel. Spin for an instant random yes or no answer to settle any question. Simple, fair and fun for quick decisions and dares.
Zodiac Sign Calculator: Free zodiac sign calculator. Enter your birth date to find your astrological star sign, its element and date range. Quick, simple and private.

Converters

Acres to Hectares Converter: Free acres to hectares converter. Convert acres to hectares instantly (1 acre = 0.404686 hectares). Live result as you type, no sign-up, private.
Angle Converter: Free angle converter. Convert between degrees, radians, gradians, arcminutes, arcseconds, and full turns instantly with exact factors, live as you type.
Area Converter: Free area converter. Convert between square meters, square feet, square kilometers, acres, hectares, square miles, and more instantly as you type.
ATM to PSI Converter: Free atm to psi converter. Convert atmospheres to pounds per square inch instantly (1 atm = 14.6959 psi). Live result as you type, no sign-up.
Bar to PSI Converter: Free bar to psi converter. Convert bar to pounds per square inch instantly (1 bar = 14.5038 psi). Live result as you type, no sign-up, private.
Binary to Decimal Converter: Free binary to decimal converter. Convert binary numbers to decimal instantly with input validation, updating live as you type. No sign-up, private.
Bits to Bytes Converter: Free bits to bytes converter. Convert bits to bytes instantly using the exact ratio (1 byte = 8 bits). Live result in your browser as you type.
Bytes to KB Converter: Free bytes to KB converter. Convert bytes to kilobytes instantly using decimal units (1 KB = 1000 bytes). Live result as you type, no sign-up, private.
Celsius to Fahrenheit Converter: Free Celsius to Fahrenheit converter. Convert C to F instantly using the correct formula (F = C x 9/5 + 32). Live result as you type, no sign-up.
Celsius to Kelvin Converter: Free Celsius to Kelvin converter. Convert C to K instantly using the exact offset (K = C + 273.15). Live result as you type, no sign-up, private.
Celsius to Rankine Converter: Free Celsius to Rankine converter. Convert C to Rankine instantly using the correct formula (R = C x 1.8 + 491.67). Live result in your browser as you type.
CM to Inches Converter: Free cm to inches converter. Convert centimeters to inches instantly using the exact factor (1 inch = 2.54 cm). Live result as you type, no sign-up.
Cooking / Recipe Converter: Free cooking measurement converter. Convert between cups, tablespoons, teaspoons, fluid ounces, and milliliters for recipes instantly as you type.
Cups to ML Converter: Free cups to ml converter. Convert US cups to milliliters instantly using the exact factor (1 cup = 236.5882365 mL). Live result as you type, private.
Data Storage Converter: Free digital storage converter. Convert between bytes, KB, MB, GB, TB, and PB using decimal (1000) or binary (1024) units, live as you type.
Decimal to Binary Converter: Free decimal to binary converter. Convert decimal numbers to binary instantly with input validation, updating live as you type. No sign-up, private.
Degrees to Radians Converter: Free degrees to radians converter. Convert degrees to radians instantly using the exact factor (pi/180). Live result in your browser as you type.
Energy Converter: Free energy converter. Convert between joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours, and BTU instantly as you type.
Fahrenheit to Celsius Converter: Free Fahrenheit to Celsius converter. Convert F to C instantly using the correct formula (C = (F - 32) x 5/9). Live result as you type, private.
Fahrenheit to Kelvin Converter: Free Fahrenheit to Kelvin converter. Convert F to K instantly using the correct formula (K = (F - 32) x 5/9 + 273.15). Live result in your browser as you type.
Feet to CM Converter: Free feet to cm converter. Convert feet to centimeters instantly using the exact factor (1 ft = 30.48 cm). Live result as you type, no sign-up.
Feet to Meters Converter: Free feet to meters converter. Convert feet to meters instantly using the exact factor (1 ft = 0.3048 m). Live result as you type, private.
Fluid Ounces to ML Converter: Free fl oz to ml converter. Convert US fluid ounces to milliliters instantly (1 fl oz = 29.5735 mL). Live result as you type, no sign-up, private.
Frequency Converter: Free frequency converter. Convert between hertz, kilohertz, megahertz, gigahertz, and RPM instantly with exact factors, updating live as you type.
Fuel Economy Converter: Free fuel economy converter. Convert between miles per gallon (US and UK) and liters per 100 km using the correct reciprocal formula, live as you type.
Gallons to Cups Converter: Free gallons to cups converter. Convert US gallons to cups instantly using the exact ratio (1 gallon = 16 cups). Live result in your browser as you type.
Gallons to Liters Converter: Free gallons to liters converter. Convert US gallons to liters instantly (1 US gallon = 3.785411784 L). Live result as you type, no sign-up, private.
GB to MB Converter: Free GB to MB converter. Convert gigabytes to megabytes instantly using decimal units (1 GB = 1000 MB). Live result as you type, no sign-up, private.
GB to TB Converter: Free GB to TB converter. Convert gigabytes to terabytes instantly using decimal units (1 TB = 1000 GB). Live result as you type, no sign-up, private.
Grams to Ounces Converter: Free grams to ounces converter. Convert grams to ounces instantly using the exact factor (1 oz = 28.3495 g). Live result as you type, no sign-up.
Hectares to Acres Converter: Free hectares to acres converter. Convert hectares to acres instantly (1 hectare = 2.47105 acres). Live result as you type, no sign-up, private.
Hex to Decimal Converter: Free hex to decimal converter. Convert hexadecimal numbers to decimal instantly with input validation, updating live as you type. No sign-up, private.
Horsepower to Watts Converter: Free horsepower to watts converter. Convert mechanical horsepower to watts instantly (1 hp = 745.7 W). Live result as you type, no sign-up, private.
Inches to CM Converter: Free inches to cm converter. Convert inches to centimeters instantly using the exact factor (1 inch = 2.54 cm). Live result as you type, private.
KB to MB Converter: Free KB to MB converter. Convert kilobytes to megabytes instantly using decimal units (1 MB = 1000 KB). Live result as you type, no sign-up, private.
KG to LBS Converter: Free kg to lbs converter. Convert kilograms to pounds instantly using the exact factor (1 kg = 2.2046226218 lb). Live result as you type, no sign-up.
KG to Stone Converter: Free kg to stone converter. Convert kilograms to stone instantly using the exact factor (1 stone = 6.35029318 kg). Live result in your browser as you type.
KM to Miles Converter: Free km to miles converter. Convert kilometers to miles instantly using the exact factor (1 km = 0.6213711922 mi). Live result as you type, private.
Knots to MPH Converter: Free knots to mph converter. Convert knots to miles per hour instantly (1 knot = 1.15078 mph). Live result as you type, no sign-up, private.
KPH to MPH Converter: Free kph to mph converter. Convert kilometers per hour to miles per hour instantly (1 mph = 1.609344 km/h). Live result as you type, no sign-up.
LBS to KG Converter: Free lbs to kg converter. Convert pounds to kilograms instantly using the exact factor (1 lb = 0.45359237 kg). Live result as you type, private.
LBS to Stone Converter: Free lbs to stone converter. Convert pounds to stone instantly using the exact factor (1 stone = 14 lb). Live result as you type, no sign-up, private.
Length Converter: Free length and distance converter. Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles instantly as you type.
Liters to Gallons Converter: Free liters to gallons converter. Convert liters to US gallons instantly (1 US gallon = 3.785411784 L). Live result as you type, no sign-up, private.
MB to GB Converter: Free MB to GB converter. Convert megabytes to gigabytes instantly using decimal units (1 GB = 1000 MB). Live result as you type, no sign-up, private.
Megabits to Megabytes Converter: Free megabits to megabytes converter. Convert Mbps to MB per second instantly (8 bits = 1 byte). Live result in your browser as you type.
Meters to Feet Converter: Free meters to feet converter. Convert meters to feet instantly using the exact factor (1 m = 3.280839895 ft). Live result as you type, private.
Miles to Feet Converter: Free miles to feet converter. Convert miles to feet instantly using the exact ratio (1 mile = 5280 feet). Live result in your browser as you type.
Miles to KM Converter: Free miles to km converter. Convert miles to kilometers instantly using the exact factor (1 mile = 1.609344 km). Live result as you type, no sign-up.
ML to Cups Converter: Free ml to cups converter. Convert milliliters to US cups instantly using the exact factor (1 cup = 236.5882365 mL). Live result as you type, no sign-up.
ML to OZ Converter: Free ml to oz converter. Convert milliliters to US fluid ounces instantly (1 fl oz = 29.5735 mL). Live result as you type, no sign-up, private.
MM to Inches Converter: Free mm to inches converter. Convert millimeters to inches instantly using the exact factor (1 inch = 25.4 mm). Live result as you type, private.
MPH to KPH Converter: Free mph to kph converter. Convert miles per hour to kilometers per hour instantly (1 mph = 1.609344 km/h). Live result as you type, private.
Ounces to Grams Converter: Free ounces to grams converter. Convert ounces to grams instantly using the exact factor (1 oz = 28.349523125 g). Live result in your browser as you type.
OZ to Grams Converter: Free oz to grams converter. Convert ounces to grams instantly using the exact factor (1 oz = 28.349523125 g). Live result as you type, no sign-up.
Pascal to PSI Converter: Free pascal to psi converter. Convert pascals to pounds per square inch instantly (1 psi = 6894.76 Pa). Live result as you type, no sign-up, private.
Pints to Milliliters Converter: Free pints to milliliters converter. Convert US pints to mL instantly using the exact factor (1 pint = 473.176473 mL). Live result in your browser as you type.
Pounds to KG Converter: Free pounds to kg converter. Convert pounds to kilograms instantly using the exact factor (1 lb = 0.45359237 kg). Live result as you type, no sign-up.
Pounds to Tons Converter: Free pounds to tons converter. Convert pounds to US short tons instantly using the exact factor (1 ton = 2000 lb). Live result in your browser as you type.
Power Converter: Free power converter. Convert between watts, kilowatts, megawatts, horsepower (metric and mechanical), and BTU per hour instantly as you type.
Pressure Converter: Free pressure converter. Convert between pascals, kilopascals, bar, psi, atmospheres, mmHg, and torr instantly with exact factors, live as you type.
PSI to Bar Converter: Free psi to bar converter. Convert pounds per square inch to bar instantly (1 bar = 14.5038 psi). Live result as you type, no sign-up, private.
Quarts to Liters Converter: Free quarts to liters converter. Convert US quarts to liters instantly using the exact factor (1 quart = 0.946352946 L). Live result in your browser as you type.
Radians to Degrees Converter: Free radians to degrees converter. Convert radians to degrees instantly using the exact factor (180/pi). Live result in your browser as you type.
Roman Numeral Converter: Free Roman numeral converter. Convert numbers to Roman numerals and Roman numerals back to numbers instantly, both directions, live as you type.
Shoe Size Converter: Free shoe size converter. Convert US, UK, EU, and centimeter shoe sizes for men and women using standard sizing tables, updating live as you type.
Speed Converter: Free speed converter. Convert between meters per second, km/h, mph, knots, and feet per second instantly with exact factors, updating live as you type.
Square Feet to Square Meters Converter: Free square feet to square meters converter. Convert ft2 to m2 instantly (1 ft2 = 0.092903 m2). Live result as you type, no sign-up, private.
Square Meters to Square Feet Converter: Free square meters to square feet converter. Convert m2 to ft2 instantly (1 m2 = 10.7639 ft2). Live result as you type, no sign-up, private.
Stone to KG Converter: Free stone to kg converter. Convert stone to kilograms instantly using the exact factor (1 stone = 6.35029318 kg). Live result as you type, private.
Stone to LBS Converter: Free stone to lbs converter. Convert stone to pounds instantly using the exact factor (1 stone = 14 lb). Live result as you type, no sign-up, private.
Tablespoons to ML Converter: Free tbsp to ml converter. Convert US tablespoons to milliliters instantly (1 tbsp = 14.7868 mL). Live result as you type, no sign-up, private.
Teaspoons to ML Converter: Free tsp to ml converter. Convert US teaspoons to milliliters instantly (1 tsp = 4.9289 mL). Live result as you type, no sign-up, private.
Teaspoons to Tablespoons Converter: Free teaspoons to tablespoons converter. Convert tsp to tbsp instantly using the exact ratio (1 tbsp = 3 tsp). Live result in your browser as you type.
Temperature Converter: Free temperature converter. Convert between Celsius, Fahrenheit, and Kelvin instantly with correct offset formulas, updating live as you type a value.
Time Converter: Free time unit converter. Convert between seconds, minutes, hours, days, weeks, months, and years instantly with exact factors, updating live as you type.
Tons to Pounds Converter: Free tons to pounds converter. Convert US short tons to pounds instantly using the exact factor (1 ton = 2000 lb). Live result in your browser as you type.
Volume Converter: Free volume converter. Convert between milliliters, liters, US and imperial gallons, quarts, pints, cups, and fluid ounces instantly as you type.
Watts to Horsepower Converter: Free watts to horsepower converter. Convert watts to mechanical horsepower instantly (1 hp = 745.7 W). Live result as you type, no sign-up, private.
Weight / Mass Converter: Free weight and mass converter. Convert between grams, kilograms, metric tonnes, ounces, pounds, and stones instantly with exact factors as you type.
Yards to Feet Converter: Free yards to feet converter. Convert yards to feet instantly using the exact ratio (1 yard = 3 feet). Live result in your browser as you type.

Color

Color Blindness Simulator: Free color blindness simulator. Enter a color to see how it appears under protanopia, deuteranopia and tritanopia to test your palette accessibility.
Color Mixer and Blender: Free color mixer and blender. Pick two colors and a blend amount to see the mixed result in HEX and RGB, with a live swatch and one-click copy.
Color Palette Generator: Free color palette generator. Pick a base color and instantly build harmonious palettes (complementary, analogous, triadic) with copyable hex codes.
Color Picker: Free visual color picker. Pick any color with the eyedropper wheel and instantly read its HEX, RGB and HSL values, then copy them with one click.
Color Shades and Tints Generator: Free shades and tints generator. Enter a base color and instantly get a full scale of darker shades and lighter tints with copyable hex codes.
CSS Gradient Generator: Free CSS gradient generator. Blend two colors, set the angle and type (linear or radial), preview live and copy the ready-to-paste background CSS.
HEX to HSL Converter: Free HEX to HSL converter. Paste a hex color code and instantly get hue, saturation and lightness as a copyable CSS hsl() string with a live swatch.
HEX to RGB Converter: Free HEX to RGB converter. Paste any hex color code and instantly get its red, green and blue values as an rgb() string ready for CSS.
HEX to RGBA Converter: Free HEX to RGBA converter. Turn a hex color and an opacity slider into a copyable CSS rgba() string, with a live checkerboard transparency preview.
Named CSS Colors Chart: Free named CSS colors chart. Browse and search all standard CSS color names with their hex codes and swatches, and copy any name or hex instantly.
Random Color Generator: Free random color generator. Generate a random color or a batch of them with one click, each shown as a swatch with copyable HEX and RGB values.
RGB to CMYK Converter: Free RGB to CMYK converter. Enter red, green and blue values and instantly get cyan, magenta, yellow and key (black) percentages for print work.
RGB to HEX Converter: Free RGB to HEX converter. Enter red, green and blue values and instantly get the matching hex color code, ready to copy into CSS or design tools.
RGB to HSL Converter: Free RGB to HSL converter. Enter red, green and blue values and instantly get hue, saturation and lightness as a copyable CSS hsl() string.
WCAG Contrast Checker: Free WCAG contrast checker. Compare a text and background color, see the exact contrast ratio and whether it passes AA and AAA accessibility levels.

Generators

API Key Generator: Free API key generator. Create random, high-entropy API keys and secret tokens with a custom prefix and length using the browser secure random source.
Barcode Generator (Code 128): Free Code 128 barcode generator. Turn any text or number into a real, scannable Code 128 barcode in your browser and download it as a PNG image.
Business and Brand Name Generator: Free business name generator. Enter a keyword and instantly get brandable company and product name ideas using prefixes, suffixes and blends. Copy any idea.
Color Hex Generator: Free color hex generator. Generate random hex color codes one at a time or in bulk, each shown with a live swatch and copyable with a single click.
Credit Card Test Number Generator: Free Luhn-valid card test number generator. Create fake numbers that pass the Luhn check for testing payment forms. For testing only, not real cards.
Emoji Favicon Generator: Free emoji favicon generator. Turn any emoji into favicon PNGs at 16, 32, 64 and 180 pixels and download them, with the HTML tag to use them.
Excuse Generator: Free excuse generator. Get a random, lighthearted excuse for being late, skipping an event or missing a deadline. Pick a category and copy the result.
Fake Data Generator: Free fake data generator. Create dummy user profiles with names, emails, addresses and phone numbers for testing and mockups, exportable as text or JSON.
Gift Idea Generator: Free gift idea generator. Stuck on what to give? Pick a recipient and interest and get random gift suggestions to spark ideas, with one-click copy.
Hashtag Generator: Free hashtag generator. Enter a topic or keywords and instantly get a set of relevant, ready-to-use hashtags for Instagram, TikTok and other social posts.
MAC Address Generator: Free MAC address generator. Create random, valid-format MAC addresses with your choice of separator and case, one or many at a time, for testing and labs.
Pickup Line Generator: Free pickup line generator. Get a random cheesy, punny or nerdy pickup line to break the ice or share a laugh. Pick a style and copy your favourite.
PIN Generator: Free PIN generator. Instantly create random numeric PIN codes of any length (4, 6 or custom) using a secure random source, one or many at a time.
QR Code Generator: Free QR code generator. Turn any URL or text into a real, scannable QR code entirely in your browser, then download it as a PNG. No sign-up, nothing uploaded.
Random Emoji Generator: Free random emoji generator. Get one or a batch of random emojis to spice up messages, usernames and posts. Click any emoji to copy it instantly.
Random Name Generator: Free random name generator. Generate realistic first and last names in bulk for characters, test data or placeholders, with one-click copy of the whole list.
Random Number Generator: Free random number generator. Pick a min and max range and generate one number or a bulk list, with an option for unique values. Copy the results instantly.
Random Password Generator (Advanced): Free advanced password generator. Build strong random passwords with fine control over length and character sets, plus a live strength meter.
Random Quote Generator: Free random quote generator. Get an inspiring or thoughtful quote at the click of a button from a built-in local collection, ready to copy and share.
Random Word Generator: Free random word generator. Get one or many random English words for brainstorming, games, writing prompts and creative exercises, with copyable output.
Slogan and Tagline Generator: Free slogan generator. Enter your brand or product and instantly get catchy tagline ideas to inspire your marketing, with one-click copy for any line.
Strong Passphrase Generator: Free passphrase generator. Build memorable, high-entropy passphrases from random words with your choice of separator, capitalization and numbers.
Username Generator: Free username generator. Instantly create catchy, available-looking usernames by mixing adjectives, nouns and numbers for gaming, social media and sign-ups.

Productivity

Aspect Ratio Calculator: Free aspect ratio calculator. Enter a width or height and get the matching dimension for any ratio like 16:9 or 4:3. Keep images in proportion.
Break Reminder Timer: Free break reminder timer. Set an interval and get a gentle on-screen and audio nudge to stand up, stretch and rest your eyes on repeat.
Emoji & Symbol Picker: Free emoji and symbol picker. Browse categories, search, and click any emoji or special character to copy it to your clipboard instantly.
Keyboard Tester: Free online keyboard tester. Press any key to see its name, key code and status light up. Check that every key on your keyboard works.
Live Word Counter: Free live word counter. Type or paste text and see words, characters, sentences, paragraphs and reading time update instantly as you write.
Meeting Cost Calculator: Free meeting cost calculator. Enter number of people, average hourly rate and duration to see what a meeting really costs, ticking up live.
Microphone Test: Free online microphone test. See a live level meter react to your voice to confirm your mic works. No recording, audio stays in your browser.
Minute Timer: Free online minute timer. Set minutes and seconds, start the count and get an alarm when time is up. Simple, private, works with no install.
Online Drawing Board: Free online drawing board. Sketch with a pen and eraser, pick colors and sizes, then download your drawing as a PNG. No sign-up, no upload.
Online Notepad: Free online notepad with autosave. Jot notes in your browser and they are saved locally as you type. No account, works offline, fully private.
Online Ruler: Free on-screen ruler in cm and inches. Measure small objects against your display. Includes a calibration slider so your DPI matches real size.
Online Signature Maker: Free online signature maker. Draw your signature with a mouse, finger or stylus and download it as a transparent PNG. Private, in your browser.
Pomodoro Timer: Free Pomodoro timer. Focus for 25 minutes, then take a 5 minute break, on repeat. Track completed sessions and stay in flow, all in browser.
Reaction Time Test: Free reaction time test. Click as soon as the box turns green and see your reaction time in milliseconds. Track your best over several tries.
Screen Resolution Checker: Free screen resolution checker. See your screen size, browser viewport, pixel ratio and color depth instantly. Live updates as you resize.
Stopwatch: Free online stopwatch with lap times. Start, stop and record splits with millisecond precision. No download, runs right in your browser.
Tally Counter: Free online tally counter. Count anything with plus and minus buttons, run several counters at once and rename them. Saved in your browser.
Team Shuffler: Free team shuffler. Paste a list of names and split them into a set number of teams or groups of a chosen size, fairly and instantly in browser.
Text to Speech: Free text to speech in your browser. Type or paste text, pick a voice, and hear it read aloud. Adjust speed and pitch, nothing uploaded.
To-Do List: Free online to-do list. Add tasks, check them off and delete when done. Saved in your browser automatically, no sign-up, works offline.
Typing Speed Test: Free typing speed test. Type the sample sentence and get your words per minute and accuracy instantly. Fun way to measure your typing skill.
Webcam Test: Free online webcam test. See a live preview of your camera in the browser to check it works before a call. No recording, nothing uploaded.

Image

Add Border to Image: Free tool to add a border to any image. Pick the border color and thickness, preview it live, and download the framed photo. Runs in your browser.
Add Text to Image: Free online tool to add text or a watermark to an image. Set the words, size, color, opacity and position, then download the labeled picture.
Blur Image: Free blur image tool. Apply an adjustable blur to any photo in your browser and download the result. Useful for backgrounds and hiding detail.
Circle Crop Image: Free circle crop tool. Cut a photo into a perfect circle with a transparent background and download it as a PNG. Ideal for profile pictures.
Grayscale Image Converter: Free grayscale image converter. Turn any photo black and white in your browser using true luminance values, then download the result. Private.
Image Color Extractor: Free image color extractor. Upload a photo and get its dominant color palette with HEX codes you can click to copy. Runs in your browser.
Image Color Picker: Free image color picker. Upload a photo, click any pixel to get its HEX and RGB values, and copy them in one click. Works in your browser.
Image Compressor: Free online image compressor. Re-encode JPG and PNG photos at a quality you choose to shrink file size, and see how much you saved. Private.
Image Cropper: Free online image cropper. Drag a crop box over your photo to keep only the part you want, then download the cropped image. Nothing uploaded.
Image Format Converter: Free online image format converter. Change a picture between PNG, JPG and WebP right in your browser and download the converted file. Private.
Image Resizer: Free online image resizer. Change an image to exact pixel dimensions or by percentage, lock the aspect ratio, and download the result. Private.
Image to Base64: Free image to Base64 converter. Turn a picture into a Base64 data URI you can paste into HTML or CSS. Copy the string, all done in your browser.
Image to WebP Converter: Free image to WebP converter. Turn JPG or PNG photos into WebP at a quality you choose, compare file sizes, and download. All in your browser.
Meme Generator: Free online meme generator. Upload any image, add classic bold top and bottom text, and download your meme. All in your browser, nothing uploaded.
Pixelate Image: Free pixelate image tool. Turn a photo into chunky pixels with an adjustable block size, great for censoring or retro art. Runs in your browser.
Placeholder Image Generator: Free placeholder image generator. Create a dummy image at any size with custom colors and label text, then download it. No upload, no server.
Rotate & Flip Image: Free online image rotator and flipper. Turn a photo left or right in 90 degree steps or mirror it horizontally and vertically, then download.
SVG to PNG Converter: Free SVG to PNG converter. Rasterize an SVG file at 1x to 8x scale and download a crisp PNG. Runs fully in your browser, nothing is uploaded.
WebP to PNG Converter: Free WebP to PNG converter. Open a WebP image in your browser and save it as a standard PNG file in one click. Private, nothing is uploaded.

PDF

Compress PDF: Free online PDF compressor. Re-save a PDF to trim its file size in your browser and see the before and after numbers. Private, nothing uploaded.
Delete PDF Pages: Free online tool to delete pages from a PDF. Remove the pages you do not want and download the trimmed document. Runs privately in your browser.
Extract PDF Text: Free online PDF text extractor. Pull the plain text out of a PDF in your browser, then copy it or download a TXT file. Nothing is uploaded anywhere.
JPG / PNG to PDF: Free online image to PDF converter. Combine JPG and PNG pictures into a single PDF, reorder them, and download. All in your browser, nothing uploaded.
Merge PDF: Free online PDF merger. Combine several PDF files into one document, drag the files to reorder them, then download the merged PDF. Nothing uploaded.
PDF Page Count & Info: Free online PDF info viewer. See a PDF page count, file size, page dimensions and metadata like title, author and producer, all in your browser.
PDF to JPG / PNG: Free online PDF to image converter. Render each page of a PDF to a JPG or PNG picture in your browser and download them. Nothing uploaded.
Reorder PDF Pages: Free online tool to reorder PDF pages. Drag page thumbnails into a new order and download the rearranged PDF. All in your browser, nothing uploaded.
Rotate PDF: Free online PDF rotator. Turn every page or selected pages of a PDF by 90, 180 or 270 degrees and download the fixed file. Private, nothing uploaded.
Split PDF: Free online PDF splitter. Pull out a page range from a PDF into a new smaller document and download it, all done privately in your browser.

Crypto

Airdrop Value Calculator: Free crypto airdrop value calculator. Enter tokens received and token price to see your airdrop value, plus per wallet value across multiple wallets.
APY to APR Converter (Crypto): Free crypto APY to APR converter. Convert between annual percentage rate and yield for any compounding frequency used in DeFi staking and lending.
BIP39 Seed Phrase Word Count Checker: Free BIP39 seed phrase word count checker. Paste a recovery phrase to verify it has a valid 12, 15, 18, 21 or 24 word length before importing.
Crypto Average Buy Price Calculator: Free crypto average buy price calculator. Enter each purchase price and coin quantity to find your weighted average cost basis and total holdings.
Crypto DCA Calculator: Free crypto dollar cost averaging calculator. Enter your buy prices and amounts to find your average cost basis, total coins and blended entry.
Crypto Leverage Calculator: Free crypto leverage calculator. Enter margin and position size to find your leverage, or enter leverage and margin to find the position you can open.
Crypto Portfolio Allocation Calculator: Free crypto portfolio allocation calculator. Enter each holding value to see percentage weights and how far each is from a target allocation to rebalance.
Crypto Position Size Calculator: Free crypto position size calculator. Enter account size, risk percent, entry and stop loss to find the position size that caps your loss per trade.
Crypto Profit Calculator: Free crypto profit calculator. Enter entry price, exit price, amount and fees to see net profit or loss, return percentage and total value instantly.
Crypto Staking Rewards Calculator: Free crypto staking rewards calculator. Enter staked amount, APR and duration to project your staking income with and without compounding.
Ethereum Address Checksum Tool: Free EIP-55 Ethereum address checksum tool. Convert a 0x address to its checksummed form and validate the mixed case checksum entirely in your browser.
Ethereum Gas Fee Calculator: Free Ethereum gas fee calculator. Enter gas price in gwei and gas limit to compute transaction cost in ETH and in dollars at any ETH price.
Ethereum Unit Converter: Free Ethereum unit converter for wei, gwei and ether. Convert between all Ethereum denominations at once with exact 18 decimal precision in your browser.
Funding Rate Calculator: Free perpetual funding rate calculator. Enter position size, funding rate and time to see the funding cost or income you pay or earn over a period.
Gwei to ETH Converter: Free Gwei to ETH and ETH to Gwei converter. Convert Ethereum gas price units instantly in your browser with full precision and no rounding errors.
Impermanent Loss Calculator: Free impermanent loss calculator for liquidity pools. Enter the price ratio change to see impermanent loss percent versus simply holding the tokens.
Liquidation Price Calculator: Free crypto liquidation price calculator for long and short leverage positions. Enter entry price, leverage and side to find your liquidation price.
Percentage To Recover Calculator: Free break even recovery calculator. Enter a drawdown percent to see the exact gain needed to get back to even, a key rule for crypto losses.
Risk Reward Ratio Calculator: Free risk reward ratio calculator for crypto trades. Enter entry, stop loss and target prices to get your risk to reward ratio and break even win rate.
ROI Multiple Calculator (Crypto): Free crypto ROI multiple calculator. Convert between a return multiple like 10x and a percentage gain, and find your profit from an investment amount.
Rule of 72 Crypto Calculator: Free rule of 72 calculator for crypto. Enter an annual return to estimate how long it takes your holdings to double, or the return needed to double in a time.
Satoshi to BTC Converter: Free Satoshi to BTC and BTC to Satoshi converter. Convert Bitcoin satoshis to whole BTC and back with exact 8 decimal precision in your browser.
Sats Per Dollar Calculator: Free sats per dollar calculator. Enter the Bitcoin price to see how many satoshis one US dollar buys and what any dollar amount is worth in sats.
Stop Loss & Take Profit Calculator: Free crypto stop loss and take profit calculator. Enter entry price and percentages to get exact stop and target prices for long or short trades.
Token Market Cap Calculator: Free token market cap and FDV calculator. Enter price, circulating supply and total supply to compute market capitalization and fully diluted valuation.
Trading Fee Breakeven Calculator: Free crypto trading fee breakeven calculator. Enter maker and taker fees to find the minimum price move needed to cover round trip trading costs.
Wei to ETH Converter: Free Wei to ETH and ETH to Wei converter. Convert the smallest Ethereum unit to ether and back with exact 18 decimal precision in your browser.

Date & Time

Add Business Days to Date: Add a number of working days to a start date, skipping weekends, to find the resulting business date and the day of the week it lands on.
Add Days to Date: Add a number of days, weeks, months or years to any date and get the exact resulting calendar date, including the day of the week.
Business Days Calculator: Count the working days between two dates, excluding weekends. See business days, total days, weekend days and full weeks in the range.
Countdown to Date and Time: A live countdown to any date and time. Watch the days, hours, minutes and seconds tick down to a launch, event or deadline in real time.
Date Difference Calculator: Find the exact difference between two dates in years, months and days, plus the total number of days, weeks, hours and minutes between them.
Date to Ordinal and Long Format: Convert a date into ordinal and long written formats. See the 1st, 2nd, 3rd style day, the full spelled out date and other common formats.
Day of the Week Finder: Find out what day of the week any date falls on, past or future. Enter a birthday or historic date and see the exact weekday instantly.
Day of the Year Calculator: Find which numbered day of the year any date is, from 1 to 365 or 366, plus how many days are left in the year and the percentage elapsed.
Days in Month Calculator: See how many days are in any month of any year, including February in leap years, plus the first and last weekday of that month.
Days Until Date: Count how many days are left until any future date. A live countdown showing days, weeks, hours and minutes remaining until your target day.
Duration Between Two Times: Work out how long is between two clock times on the same day or overnight. Get the gap in hours and minutes and in decimal hours.
Hours Worked Calculator: Calculate total hours worked from a clock in and clock out time, minus break minutes. Shows hours and minutes plus decimal hours for pay.
ISO Week Number Calculator: Find the ISO 8601 week number for any date, plus the week year, the day of the week and the range of dates that week covers.
Leap Year Checker: Check whether any year is a leap year and see why. Lists the next several leap years and shows how many days that year has.
Live Unix Time Clock: A live clock showing the current Unix epoch time in seconds and milliseconds, plus the matching UTC and local date and time, updating each second.
Moon Phase Calculator: Find the moon phase for any date. See the phase name, illumination percent and the moon age in days, computed from the lunar cycle.
Next Birthday Countdown: Count down to your next birthday. Enter your birth date to see the days until it, the weekday it falls on, and the age you will turn.
Quarter of the Year Finder: Find which fiscal quarter a date falls in. See the quarter number, its start and end dates, and how many days are left in that quarter.
Sleep Bedtime Calculator: Find the best times to go to sleep or wake up based on 90 minute sleep cycles, so you wake between cycles feeling more refreshed.
Subtract Days from Date: Subtract days, weeks, months or years from any date to find a past calendar date, complete with the exact day of the week it falls on.
Time Ago Calculator: Turn a past date and time into a plain time ago phrase like 3 days ago or 5 months ago, plus the exact elapsed days, hours and minutes.
Time Duration Calculator: Add or subtract times in hours, minutes and seconds. Combine multiple durations and get the total in HH:MM:SS and in decimal hours.
Time Lived Calculator: See how long you have been alive in total days, hours, minutes and seconds from your birth date, updated live down to the second.
Week of the Month Finder: Find which week of the month a date falls in and which occurrence of that weekday it is, like the second Tuesday or the last Friday.
Weekday Occurrence Counter: Count how many times each weekday occurs between two dates. See exactly how many Mondays, Fridays or any weekday fall in your date range.
Weekly Timesheet Calculator: Add up hours across a full week from daily clock in and clock out times with breaks. See each day and the weekly total in decimal hours.
World Time Zone Converter: Convert a time from one time zone to another using real IANA zones. Pick a date and time, choose two cities, and see the matching local time.

Data

CSV Column Extractor: Free CSV column extractor. Pull a single column out of a CSV file by name or number, with a real parser that respects quoted fields and commas.
CSV to Markdown Table: Free CSV to Markdown table converter. Turn CSV data into a clean GitHub flavored Markdown table with aligned columns for READMEs, docs and issues.
CSV to SQL Insert: Free CSV to SQL insert generator. Turn CSV rows into ready to run INSERT statements with a header derived column list and safely quoted values.
CSV to TSV: Free CSV to TSV converter. Turn comma separated values into tab separated text you can paste straight into spreadsheets, respecting quoted fields.
CSV Transpose: Free CSV transpose tool. Flip rows and columns of a CSV so headers become the first column, using a real parser that respects quoted fields.
Fixed Width to CSV: Free fixed width to CSV converter. Split fixed column mainframe or report text into CSV by specifying column widths, trimming padding from each field.
JSON Array to NDJSON: Free JSON array to NDJSON converter. Turn a JSON array into newline delimited JSON, one compact record per line, ready for streaming and log tools.
JSON Flatten: Free JSON flatten tool. Collapse a nested JSON object into flat dot notation keys, turning deep structures into a single level map for easy diffing.
JSON Keys Extractor: Free JSON keys extractor. List every unique key path in a JSON document, including nested objects and arrays, so you can map or document a payload.
JSON Path Extractor: Free JSON path extractor. Pull a value from deep inside JSON using a dot and bracket path like user.tags[0], with clear errors when a path is missing.
JSON Sort Keys: Free JSON key sorter. Sort every object key alphabetically at all nesting levels for deterministic diffs, cleaner configs and reproducible output.
JSON Stringify Viewer: Free JSON stringify tool. Parse and re serialize JSON with a chosen indent, or produce an escaped single string value ready to embed in code.
JSON to ENV: Free JSON to env file converter. Turn a flat JSON object into dotenv KEY=value lines, upper casing keys and quoting values that contain spaces.
JSON to Go Struct: Free JSON to Go struct converter. Generate typed Go structs with json tags from a JSON sample, inferring nested types, slices and field names.
JSON to HTML Table: Free JSON to HTML table converter. Turn an array of JSON objects into a clean HTML table with a header row and escaped cells, ready to paste anywhere.
JSON to PHP Array: Free JSON to PHP array converter. Turn JSON into a valid PHP array literal using short bracket syntax, ready to paste into a config or fixture file.
JSON to Query String: Free JSON to query string converter. Turn a JSON object into a URL encoded query string, flattening nested objects and arrays with bracket notation.
JSON to TOML: Free JSON to TOML converter. Turn JSON config into TOML tables and key value pairs for Rust, Python and other tools that read TOML config files.
JSON to TypeScript: Free JSON to TypeScript converter. Generate a typed interface from a JSON sample, inferring nested objects, arrays and optional fields automatically.
JSON to XML: Free JSON to XML converter. Turn JSON objects and arrays into clean, indented XML for legacy APIs, SOAP services, config files and data feeds.
JSON Unescape: Free JSON unescape tool. Turn an escaped JSON string back into readable text, decoding backslash escapes, quotes, newlines and unicode sequences.
JSON Unflatten: Free JSON unflatten tool. Rebuild a nested JSON object from flat dot notation keys, expanding paths and array indices back into real structure.
List to JSON Array: Free list to JSON array converter. Turn a plain list of lines into a JSON array of strings or numbers, trimming blanks and optionally deduplicating.
NDJSON to JSON Array: Free NDJSON to JSON array converter. Turn newline delimited JSON into a single JSON array, parsing each line and reporting any bad rows clearly.
Query String to JSON: Free query string to JSON converter. Parse a URL query string into a clean JSON object, decoding values and grouping repeated keys into arrays.
TSV to CSV: Free TSV to CSV converter. Turn tab separated values into proper comma separated CSV, quoting fields that contain commas, quotes or line breaks.
XML to JSON: Free XML to JSON converter. Parse XML documents into clean, readable JSON with attributes and repeated elements handled correctly in your browser.

SEO

Anchor Text Suggester: Free anchor text suggester. Enter a keyword and target URL to get varied, natural anchor text ideas across exact, partial, branded and generic types.
Article Schema (JSON-LD) Generator: Free Article schema generator. Enter headline, author, dates and image to build valid Article JSON-LD structured data for richer news and blog results.
Breadcrumb Schema (JSON-LD) Generator: Free breadcrumb schema generator. Enter your page path steps to build valid BreadcrumbList JSON-LD structured data for cleaner breadcrumb search results.
Canonical Tag Generator: Free canonical tag generator. Enter your preferred page URL to create a valid rel canonical link tag and stop duplicate content from splitting your rankings.
CTR & Ad Metrics Calculator: Free CTR calculator. Enter impressions, clicks, conversions and spend to compute click through rate, conversion rate, CPC, CPA and ROAS instantly.
FAQ Schema (JSON-LD) Generator: Free FAQ schema generator. Add questions and answers to build valid FAQPage JSON-LD structured data that can earn rich results in Google search.
Google SERP Snippet Preview: Free Google SERP snippet preview. Type your title, URL and meta description to see a live desktop and mobile search result with pixel-width truncation.
Hreflang Tag Generator: Free hreflang tag generator. Map languages and regions to URLs to build valid hreflang link tags with x-default for correct international SEO targeting.
Keyword Combiner & Mixer: Free keyword mixer. Combine two or three lists of words into every keyword phrase permutation for PPC and SEO, with optional match type brackets.
Keyword Density Checker: Free keyword density checker. Paste your content to see word and phrase frequency, density percentages and total word count. Spot keyword stuffing fast.
Meta Description Length Checker: Free meta description length checker. Count characters and pixel width and see if Google will truncate your description on desktop and mobile. Private.
Noindex Meta Tag Generator: Free noindex tag generator. Build a robots meta tag with noindex, nofollow, noarchive and other directives to keep pages out of search results. Private.
Open Graph Tag Generator: Free Open Graph generator. Enter title, description, image and type to build valid og meta tags for rich link previews on Facebook, LinkedIn and Slack.
Organization Schema (JSON-LD) Generator: Free Organization schema generator. Build valid JSON-LD structured data with your name, logo, URL and social profiles to boost brand knowledge panels.
Page Weight Budget Calculator: Free page weight calculator. Add HTML, CSS, JS, image and font sizes to see total page weight and estimated load time across 3G, 4G and broadband speeds.
Product Schema (JSON-LD) Generator: Free Product schema generator. Enter name, price, currency, availability and rating to build valid Product JSON-LD structured data for rich shopping results.
Reading Time Calculator: Free reading time calculator. Paste text to estimate how long it takes to read, with word count, sentence count and separate speaking time for scripts.
SEO Content Score Checker: Free SEO content checker. Paste your article and target keyword to score word count, keyword usage, headings and readability against on-page best practices.
Sitemap XML Generator: Free sitemap XML generator. Paste a list of URLs to build a valid XML sitemap with lastmod, changefreq and priority, ready to submit to search engines.
Title Tag Length Checker: Free title tag length checker. Measure your SEO title in characters and pixels and see if Google will truncate it on desktop and mobile. Instant, private.
Twitter Card Meta Tag Generator: Free Twitter card generator. Enter title, description, image and handles to build valid twitter card meta tags for rich link previews on X and Twitter.
UTM Campaign Link Builder: Free UTM link builder. Add source, medium, campaign, term and content parameters to any URL and copy a clean, trackable campaign link for analytics.
YouTube Tag & Description Builder: Free YouTube tag builder. Turn your video topic keywords into comma separated tags and a description with timestamps and hashtags for better discovery.

Social

Best Time to Post Reference: Reference of generally recommended best times to post on Instagram, X, Facebook, TikTok, LinkedIn and Pinterest, adjusted to your local timezone.
Call to Action Generator: Generate call to action ideas for social posts by goal: get comments, saves, shares, follows, clicks or sign ups. Copy a fresh CTA in one click.
Discord Timestamp Generator: Generate Discord timestamp codes that show the right local time for everyone. Pick a date, time and style to get the <t:unix:style> code.
Emoji Copy Picker: Browse a categorized emoji grid and click any emoji to copy it. Search by name, filter by category, and build a string of emoji for your posts.
Engagement Rate Calculator: Calculate social media engagement rate from likes, comments, shares and saves. Get rate by followers and by reach with a quality benchmark.
Follower to Following Ratio Calculator: Work out your followers to following ratio and see what it signals. Enter both counts to get the ratio, a percentage and a quick read.
Hashtag Counter: Count the hashtags in a caption and check against Instagram, TikTok and X limits. Lists each unique tag and flags duplicates instantly.
Hashtag Set From Keywords: Turn keywords or a caption into a ready to paste hashtag set. Generates camel case and lowercase tags and dedupes them automatically.
Instagram Bio Generator: Create a punchy Instagram bio from your name, role and interests. Builds a stacked bio with emoji and a call to action under 150 characters.
Instagram Caption Generator: Generate Instagram caption ideas from your topic with a hook, body, emoji and a call to action. Pick a tone and copy the caption instantly.
Instagram Line Break Generator: Add real line breaks and spacing to Instagram captions and bios that survive posting. Inserts invisible characters so gaps do not collapse.
Multi Platform Character Counter: Count your text against every social media limit at once: X, Instagram, TikTok, LinkedIn, Facebook, YouTube, Threads and Bluesky.
Reels Hashtag Set Generator: Build a balanced Instagram Reels hashtag set that mixes broad, medium and niche tags around your topic, sized to stay under the 30 tag cap.
Social Media Image Size Reference: Reference table of current image and video dimensions for Instagram, X, Facebook, TikTok, YouTube, LinkedIn and Pinterest. Search and copy sizes.
TikTok Money Calculator: Estimate TikTok earnings from views using a per thousand view rate. See low, average and high estimates for a video and a monthly total.
Tweet Character Counter: Free tweet character counter that respects X limits, counts each URL as 23 characters, and shows how many tweets long text needs.
Twitter Bio Generator: Generate a tight X bio from your role, focus and vibe. Builds a bio under the 160 character limit with separators and an optional link cue.
Twitter Thread Splitter: Split long text into a numbered X thread with each tweet kept under 280 characters. Breaks on word boundaries and adds 1/n numbering.
YouTube Money Calculator: Estimate YouTube ad revenue from views and RPM. Enter monthly views and a realistic RPM to see daily, monthly and yearly income ranges.
YouTube Tag Extractor: Extract clean comma separated YouTube tags from a block of text or keywords. Dedupes, trims, and counts against the 500 character tag budget.
YouTube Timestamp Link Generator: Turn a YouTube URL and a time into a link that jumps to that moment. Also builds chapter timestamp lists for your video description.
YouTube Title Length Checker: Check YouTube title length so it does not get cut off. See character count against the 100 cap and the roughly 60 char display truncation point.

Network

CIDR Calculator: Free CIDR calculator. Enter an IPv4 CIDR block and get the network address, broadcast, usable host range, subnet mask and total host count instantly.
CIDR to Netmask Converter: Free CIDR to netmask converter. Turn a CIDR prefix like /26 into its dotted decimal subnet mask and back again instantly, all in your browser.
DNS Record Types Reference: Free DNS record types reference. Search common DNS record types like A, AAAA, MX and TXT and read what each one does, offline in your browser.
HTTP Header Reference: Free HTTP header reference. Search common request and response headers and read what each one does, whether offline in your browser, no lookups needed.
HTTP Status Code Lookup: Free HTTP status code reference. Search every standard HTTP status code by number or name and read its meaning and category, all offline in your browser.
IP to Binary Converter: Free IP to binary converter. See any IPv4 address as its 32-bit binary form, octet by octet, plus hex and integer, all computed instantly in your browser.
IP to Integer Converter: Free IP to integer converter. Turn a dotted decimal IPv4 address into its single 32-bit unsigned integer, and convert an integer back to an IP, in your browser.
IPv4 and IPv6 Validator: Free IP address validator. Check whether a string is a valid IPv4 or IPv6 address and see its type, class and whether it is private, all in your browser.
IPv4 Range Calculator: Free IPv4 range calculator. Enter a start and end IPv4 address and get the exact number of addresses in the inclusive range, all computed in your browser.
IPv6 Expander and Compressor: Free IPv6 expander and compressor. Expand a shortened IPv6 address to its full form or compress a long one to the shortest valid form, in your browser.
MAC Address Formatter: Free MAC address formatter. Normalize a MAC address and convert it between colon, hyphen, dot and bare hex separators, uppercase or lowercase, in your browser.
MIME Type Lookup: Free MIME type lookup. Find the correct Content-Type for any file extension, or search by type, instantly and offline in your browser, no server needed.
Netmask to CIDR Converter: Free netmask to CIDR converter. Paste a dotted decimal subnet mask and get its CIDR prefix length, with validation for contiguous masks, in your browser.
Punycode Domain Converter: Free punycode converter. Turn an international domain name into its ASCII punycode form and back, using the browser URL engine, all offline in your browser.
Query String Builder: Free query string builder. Enter key and value pairs and get a correctly URL encoded query string ready to append to any link, built in your browser.
Query String to Table: Free query string parser. Paste a URL query string and see every parameter listed as clean key and value rows, decoded and easy to read, in your browser.
Subnet Mask Calculator: Free subnet mask calculator. Pick a CIDR prefix and see the matching dotted decimal mask, wildcard mask, binary form and host count, all in your browser.
URL Parser: Free online URL parser. Break any URL into protocol, host, port, path, query string and hash instantly in your browser using the native URL API.
URL Query Value Encoder: Free URL query value encoder and decoder. Percent encode a single value for safe use in a query string, or decode one back, all in your browser.
User Agent Parser: Free user agent parser. Paste any browser user agent string and read the likely browser, engine, operating system and device type, all parsed in your browser.
Well Known Ports Lookup: Free port number lookup. Search common TCP and UDP ports by number or service name and see what each one is used for, offline in your browser.
WHOIS Lookup Link Builder: Free WHOIS lookup link builder. Enter a domain and get ready to open WHOIS and DNS lookup links for several services, built entirely in your browser.

Science

Acceleration Calculator: Free acceleration calculator. Find acceleration from the change in velocity over time using a equals delta v over t, or solve for velocity or time.
Capacitor Code Calculator: Free capacitor code calculator. Enter a 3 digit ceramic capacitor code like 104 and get the capacitance in picofarads, nanofarads and microfarads.
Decibel (dB) Calculator: Free decibel calculator. Convert a power or amplitude ratio to decibels and back, using 10 log for power and 20 log for voltage or amplitude ratios.
Density Calculator: Free density calculator. Solve for density, mass, or volume using density equals mass over volume. Enter any two values and get the third instantly.
Force Calculator (F = ma): Free force calculator using Newton's second law. Solve for force, mass, or acceleration with F equals m times a. Enter any two and get the third.
Gravitational Potential Energy Calculator: Free gravitational potential energy calculator. Compute PE from mass, gravity and height using PE equals m g h, or solve for any missing value.
Half-Life Calculator: Free half-life calculator. Find the remaining amount of a decaying substance after a given time, or work out its half-life from an amount and elapsed time.
Ideal Gas Law Calculator: Free ideal gas law calculator. Solve PV equals nRT for pressure, volume, moles or temperature. Enter any three values using SI units and get the fourth.
Kinetic Energy Calculator: Free kinetic energy calculator. Compute kinetic energy from mass and velocity, or solve for mass or speed, using KE equals one half m v squared.
Molar Mass Calculator: Free molar mass calculator. Type a chemical formula like H2O or Ca(OH)2 and get its molar mass in grams per mole with a per element breakdown.
Molarity Calculator: Free molarity calculator. Solve for molar concentration, moles of solute, or solution volume using M equals moles divided by liters. Enter any two.
Ohm's Law Calculator: Free Ohm's law calculator. Enter any two of voltage, current, resistance or power and instantly solve for the other two using V=IR and P=VI.
Percent Error Calculator: Free percent error calculator. Compare a measured value against the true value and get the absolute error and percent error for lab reports instantly.
pH Calculator: Free pH calculator. Convert between hydrogen ion concentration and pH, find pOH and hydroxide concentration, and classify a solution as acid or base.
Projectile Range Calculator: Free projectile motion calculator. Enter launch speed and angle to find range, maximum height and flight time for a projectile on level ground.
Resistor Color Code Calculator: Free resistor color code calculator. Pick the bands on a 4, 5 or 6 band resistor and read the resistance value, tolerance and temperature coefficient.
Scientific Notation Converter: Free scientific notation converter. Convert any decimal number to scientific and E notation, or expand scientific notation back to a plain decimal.
Significant Figures Counter: Free significant figures counter and rounder. Count the sig figs in any number and round it to a chosen number of significant figures instantly.
Specific Heat Calculator: Free specific heat calculator. Solve the heat equation Q equals m c delta T for heat energy, mass, specific heat or temperature change. Enter any three.
Speed Distance Time Calculator: Free speed distance time calculator. Solve for speed, distance or time using speed equals distance over time. Enter any two values and get the third.
Torque Calculator: Free torque calculator. Compute torque from force, lever arm length and angle using tau equals force times radius times the sine of the angle.
Voltage Divider Calculator: Free voltage divider calculator. Enter the input voltage and two resistor values to find the output voltage using Vout equals Vin times R2 over R1 plus R2.
Wavelength Frequency Converter: Free wavelength to frequency converter. Convert between wavelength and frequency for light or any wave using c equals lambda times f. Set the wave speed.
Weight on Other Planets Calculator: Free weight on planets calculator. Enter your weight on Earth to see what you would weigh on the Moon, Mars, Jupiter and every planet in the solar system.

Math

Arithmetic Series Sum Calculator: Free arithmetic series calculator. Sum an arithmetic sequence from its first term, common difference and length, or find the nth term instantly.
Base Converter (Any Base 2 to 36): Free base converter for any radix from 2 to 36. Convert a number between binary, octal, decimal, hex and any custom base with one entry.
Decimal to Fraction Converter: Free decimal to fraction converter. Turn any decimal into its exact simplified fraction, including repeating decimals, plus a mixed number form.
Distance Between Two Points Calculator: Free distance between two points calculator. Use the distance formula to find the straight-line length between two coordinates, with the steps shown.
Exponent Calculator: Free exponent calculator. Raise any base to any power, including negative and fractional exponents, and see the exact or precise decimal result.
Factorial Calculator: Free factorial calculator. Compute n factorial for any non-negative integer, with exact big-integer results and no rounding for large inputs.
Fibonacci Sequence Generator: Free Fibonacci sequence generator. Produce the first N Fibonacci numbers with exact big-integer values, plus the nth term and running sum.
Fraction to Decimal Converter: Free fraction to decimal converter. Turn any fraction into its decimal value and percentage, and see repeating digits marked clearly.
GCF of a List Calculator: Free greatest common factor calculator. Find the GCF of many numbers at once using the Euclidean algorithm, exact for very large values.
LCM of a List Calculator: Free LCM of a list calculator. Find the least common multiple of many numbers at once, using exact big-integer math so large results stay precise.
Logarithm Calculator: Free logarithm calculator. Compute the log of any positive number in any base, including natural log and log base 10, with the exponent check shown.
Mean, Median, Mode and Range Calculator: Free mean, median, mode and range calculator. Paste a list of numbers and get all four measures of center and spread instantly, with the count and sum.
Midpoint Calculator: Free midpoint calculator. Find the exact midpoint between two coordinates using the midpoint formula, averaging the x and y values.
Modulo Calculator: Free modulo calculator. Find the remainder of a division, plus the quotient and the true mathematical modulo, for any two numbers instantly.
Number to Words Converter: Free number to words converter. Spell any whole number in plain English, from zero up into the trillions, for checks, contracts and homework.
Percentage Increase and Decrease Calculator: Free percentage increase and decrease calculator. Find the percent change between two numbers and the new value after applying a percentage.
Permutation and Combination Calculator: Free permutation and combination calculator. Compute nPr and nCr for any n and r using exact big-integer math, with the factorial formulas shown.
Prime Factorization Calculator: Free prime factorization calculator. Break any whole number into its prime factors and see the result in expanded and exponent form instantly.
Prime Number Checker: Free prime number checker. Enter any whole number and instantly see whether it is prime or composite, with its smallest factor when it is not.
Probability Calculator: Free probability calculator. Find the probability of single and combined events, including AND, OR, and NOT, as a fraction, decimal and percentage.
Proportion Solver (Solve for X): Free proportion solver. Cross multiply to solve for the missing value in a proportion a over b equals c over x, with the work shown.
Ratio Simplifier: Free ratio simplifier. Reduce any ratio to its simplest whole-number form and see the decimal equivalent, using the greatest common divisor.
Rounding Calculator (Decimals and Sig Figs): Free rounding calculator. Round any number to a set number of decimal places, significant figures, or the nearest ten, hundred or thousand.
Scientific Notation to Decimal: Free scientific notation converter. Switch between standard decimal numbers and scientific notation both ways, with the E-notation form shown too.
Slope Calculator (Two Points): Free slope calculator. Enter two points and get the slope, the line equation, the angle in degrees, and the y-intercept instantly.
Triangle Area Calculator (Heron Formula): Free triangle area calculator. Find the area of any triangle from its three sides using Heron formula, or from a base and height, instantly.

Finance

50/30/20 Budget Calculator: Free 50/30/20 budget calculator. Split your monthly take home pay into needs, wants, and savings using the popular 50/30/20 budgeting rule.
Annuity Payment Calculator: Free annuity payment calculator. Find the fixed periodic payment a lump sum can provide, or the payout from a present value over a set term.
Coast FIRE Calculator: Free Coast FIRE calculator. Find the amount you need invested today so compound growth alone funds retirement without adding another dollar.
Cost of Living Difference Calculator: Free cost of living calculator. Compare two cities by index and find the salary you need to keep the same standard of living after moving.
Debt Avalanche Calculator: Free debt avalanche calculator. Target the highest interest rate debt first to minimize total interest, and see your months to payoff and interest saved.
Debt Snowball Calculator: Free debt snowball calculator. Order your debts smallest balance first, apply a monthly extra payment, and see your payoff order and months to debt free.
Discount and Tax Calculator: Free discount and tax calculator. Apply a percent discount then add sales tax to get the final checkout price, the amount saved, and the tax charged.
Dollar Cost Averaging Calculator: Free dollar cost averaging calculator. Project a recurring investment growing at a steady return and see contributions versus interest earned.
Effective Hourly Rate Calculator: Free effective hourly rate calculator. Reveal what you truly earn per hour once commute and unpaid work hours are added to your paid time.
FIRE Number Calculator: Free FIRE number calculator. Find how much you need invested to retire early using the 4 percent rule, plus years to reach financial independence.
Future Value Calculator: Free future value calculator. Find what a lump sum plus regular contributions grows to with compound interest over a set number of years.
Hourly to Salary Calculator: Free hourly to salary calculator. Convert an hourly wage into an annual salary using your weekly hours and weeks worked per year.
Inflation Calculator: Free inflation calculator. See how much future buying power your money loses over time, or what an amount will be worth after years of inflation.
Lump Sum vs Payments Calculator: Free lump sum vs payments calculator. Compare taking a cash lump sum now against a stream of future payments using present value and a discount rate.
Present Value Calculator: Free present value calculator. Discount a future amount back to what it is worth today using a discount rate and a number of periods.
Raise Percentage Calculator: Free raise calculator. Find your pay raise as a percentage and dollar amount, or work out your new salary from a given raise percentage.
Real Rate of Return Calculator: Free real rate of return calculator. Convert a nominal investment return into the inflation adjusted real return using the exact Fisher equation.
Rule of 114 Calculator: Free rule of 114 calculator. Estimate the years to triple your money at a given annual return, plus the rate needed to triple in a set time.
Salary to Hourly Calculator: Free salary to hourly calculator. Convert an annual salary into an hourly wage based on your weekly hours and weeks worked per year.
Savings Rate Calculator: Free savings rate calculator. Find the percentage of your income you save each month and see how it compares to common financial independence targets.
Sinking Fund Calculator: Free sinking fund calculator. Work out the monthly amount to set aside to reach a savings target by a deadline, with or without interest.
Take Home Pay Estimator: Free take home pay estimator. Enter gross salary and deduction percentages to estimate net pay per year, month, and paycheck instantly.
Time to Reach Savings Goal Calculator: Free savings timeline calculator. Find how many months and years it takes to reach a savings goal given your deposits and interest rate.
Tip and Split Calculator: Free tip and split calculator. Add a tip, optionally round the total, and split the bill evenly across any number of people for a clean per person amount.

Health & Fitness

Blood Alcohol Content Calculator: Free blood alcohol content estimator. Approximate BAC from drinks, weight, sex, and time using the Widmark formula, all in your browser.
BMI Prime Calculator: Free BMI Prime calculator. See your BMI as a ratio to the upper healthy limit of 25, with category, computed instantly in your browser.
Body Surface Area Calculator: Free body surface area calculator. Estimate BSA in square metres using the Mosteller and Du Bois formulas, side by side, in your browser.
Calorie Deficit Calculator: Free calorie deficit calculator. Enter maintenance calories and a target loss rate to see your daily deficit and adjusted intake, computed in your browser.
Calories to Kilojoules Converter: Free calories to kilojoules converter. Switch between food calories and kilojoules instantly, both directions, all in your browser.
Daily Water Intake in Ounces Calculator: Free water intake calculator in ounces. Estimate daily fluid needs from body weight and activity, shown in ounces, cups, and litres, in your browser.
Lean Body Mass Calculator: Free lean body mass calculator. Estimate lean mass and fat mass from weight and body fat, or the Boer formula, all in your browser.
Macro Split Calculator: Free macro split calculator. Turn your daily calorie target into protein, carb, and fat grams using a percentage split you choose, all in your browser.
Max Heart Rate Calculator: Free max heart rate calculator. Estimate your maximum heart rate from age using two proven formulas, side by side, all in your browser.
One Rep Max Multi Formula Calculator: Free one rep max calculator with four formulas. Estimate your 1RM from weight and reps using Epley, Brzycki, Lombardi, and Lander in your browser.
Ovulation Window Calculator: Free ovulation window calculator. Estimate your fertile window and likely ovulation day from your last period and cycle length, in your browser.
Ponderal Index Calculator: Free ponderal index calculator. Compute the corpulence index using weight divided by height cubed, worked out instantly in your browser.
Pregnancy Week Calculator: Free pregnancy week calculator. Find your current gestational week, trimester, and days remaining from your last period, in your browser.
Protein Intake Calculator: Free daily protein intake calculator. Estimate grams of protein per day from your body weight and activity goal, worked out instantly in your browser.
Race Finish Time Predictor: Free race time predictor. Estimate your finish time at a new distance from a recent race using the Riegel formula, computed in your browser.
Reps Per Minute Pace Calculator: Free reps per minute calculator. Turn a total rep goal and time limit into a pace, sets, and rest plan for pushups or any exercise, in your browser.
Running Pace to Speed Converter: Free running pace to speed converter. Turn minutes per kilometre or mile into km/h and mph, and back again, instantly in your browser.
Sleep Debt Calculator: Free sleep debt calculator. Compare your recent sleep against a nightly goal to see your accumulated sleep debt for the week, in your browser.
Smoking Cost Calculator: Free smoking cost calculator. See how much cigarettes cost you per week, month, year, and decade based on packs and price, in your browser.
Steps to Distance Calculator: Free steps to distance calculator. Convert your step count into kilometres and miles using your height or a custom stride, in your browser.
Target Heart Rate Zone Calculator: Free target heart rate zone calculator. Get Karvonen training zones from your age and resting heart rate, calculated instantly in your browser.
VO2 Max Estimator: Free VO2 max estimator. Approximate your aerobic fitness from a one mile walk test or resting heart rate, calculated in your browser.
Waist to Height Ratio Calculator: Free waist to height ratio calculator. Divide waist by height and see the healthy range guideline, worked out instantly in your browser.
Waist to Hip Ratio Calculator: Free waist to hip ratio calculator. Divide waist by hip measurement and see the WHO health category by sex, computed instantly in your browser.

Education

Attendance Percentage Calculator: Calculate your attendance percentage from classes attended and total held, and see how many you can still miss to stay above a required minimum.
Class Rank Percentile Calculator: Convert your class rank and class size into a percentile and top percent. Free class rank percentile calculator for high school and college.
College GPA Calculator: Free college GPA calculator with credit hours. Enter each course grade and credits to compute your college GPA on the standard 4.0 university scale.
Credit Hours to Study Time Calculator: Estimate weekly study hours and total workload from your enrolled credit hours using the standard two hours of study per credit guideline.
Exam Countdown Calculator: Count down to your exam date and see days, weeks and study days left, plus suggested daily study time to cover your material in time.
Final Exam Grade Needed Calculator: Find the score you need on your final exam to hit your target grade. Enter your current grade, the target and the final worth to get the answer.
Grade Calculator: Free weighted grade calculator by category. Enter your scores and the weight of each category to compute your overall course grade and letter.
Grade Curve Calculator: Apply a class curve to a raw score. Free grade curve calculator supporting flat point boost, square root curve and top score scaling methods.
Grade Impact Planner: See how a future assignment score changes your overall grade before you submit it. Free grade impact planner using current grade and item weight.
High School GPA Calculator: Free high school GPA calculator on the 4.0 unweighted scale. Enter your class grades to instantly find your high school grade point average.
IB Diploma Points Calculator: Add up your IB subject grades plus the extended essay and theory of knowledge bonus to get your total out of 45 and check if you pass the diploma.
Letter Grade Calculator: Convert a percentage score into a letter grade and 4.0 grade point instantly. Free percentage to letter grade calculator with a full scale table.
Pass or Fail Grade Calculator: Check if your score passes and how far you are from the passing mark. Free pass or fail calculator with a custom passing threshold for any test.
Percentage to 4.0 GPA Converter: Convert a percentage grade into a 4.0 scale GPA value and letter grade. Free percentage to GPA converter for transcripts and study abroad applications.
Points Needed to Pass Calculator: Work out how many more points you need to reach your target grade. Free points needed calculator using points earned out of total points possible.
Reading Assignment Time Estimator: Estimate how long a reading assignment will take from page or word count, difficulty and your reading speed. Free study planner for students.
Semester GPA Calculator: Free semester GPA calculator. Enter each class letter grade and credit hours for one term to get your semester grade point average on a 4.0 scale.
Spaced Repetition Interval Calculator: Generate spaced repetition review dates for a flashcard using a Leitner style schedule. Free spaced repetition interval calculator for studying.
Study Time Planner: Split your available study hours across subjects by priority weight. Free study time planner that shows how many hours to give each subject per week.
Test Score Percentage Calculator: Convert correct answers out of total questions into a percentage and letter grade. Free instant test and quiz score calculator for students.
Weighted Average Grade Calculator: Average several grades where each has a different weight. Free weighted average grade calculator for combining tests, projects and homework fairly.
Weighted GPA Calculator: Free weighted GPA calculator for high school. Add course grades, credit hours and class level (regular, honors, AP or IB) to get your weighted GPA.

Business

Average Order Value Calculator: Free average order value calculator. Divide total revenue by number of orders to find AOV instantly, right in your browser. No signup needed.
Break Even Units Calculator: Free break even units calculator. Enter fixed costs, price and variable cost per unit to find the units and revenue needed to break even.
Burn Rate and Runway Calculator: Free burn rate and runway calculator. Enter cash, monthly spend and income to find net burn and how many months of runway remain.
CAC Payback Period Calculator: Free CAC payback period calculator. Find how many months it takes to recover acquisition cost from customer gross profit, right in your browser.
Churn Rate Calculator: Free churn rate calculator. Enter customers lost and starting customers to get churn rate and retention rate percent instantly in your browser.
Conversion Rate Calculator: Free conversion rate calculator. Divide conversions by visitors to get your conversion rate percent, plus visitors needed per goal, in your browser.
Cost Plus Pricing Calculator: Free cost plus pricing calculator. Add material, labor and overhead, apply a markup, and get your selling price and profit per unit instantly.
Customer Acquisition Cost Calculator: Free CAC calculator. Divide your sales and marketing spend by new customers to find customer acquisition cost instantly in your browser.
Customer Lifetime Value Calculator: Free LTV calculator. Enter average order value, purchase frequency, lifespan and margin to estimate customer lifetime value in your browser.
EBITDA Margin Calculator: Free EBITDA margin calculator. Enter revenue, expenses, depreciation and amortization to get EBITDA and EBITDA margin percent in your browser.
Employee Cost Calculator: Free employee cost calculator. Add salary, payroll taxes, benefits and overhead to find the true annual and hourly cost of an employee.
Freelance Hourly Rate Calculator: Free freelance hourly rate calculator. Turn a target salary, expenses and billable hours into the hourly rate you must charge, in your browser.
Gross Profit Calculator: Free gross profit calculator. Enter revenue and cost of goods sold to get gross profit and gross margin percent instantly in your browser.
Invoice Total Calculator: Free invoice total calculator. Add line items, apply a discount and tax, and get the subtotal, tax and grand total instantly in your browser.
LTV to CAC Ratio Calculator: Free LTV to CAC ratio calculator. Compare lifetime value against acquisition cost to judge if your unit economics are healthy, all in your browser.
Margin vs Markup Calculator: Convert between margin and markup. Enter one percentage to see the other, plus the price built from your cost. Fast, browser side, no signup.
Markup Calculator: Free markup calculator. Enter cost and markup percent to get the selling price, profit and resulting margin instantly in your browser.
MRR and ARR Calculator: Free MRR and ARR calculator. Turn subscribers and average price into monthly and annual recurring revenue instantly, all in your browser.
Net Profit Margin Calculator: Free net profit margin calculator. Enter revenue and total expenses to get net profit and net margin percent instantly, all in your browser.
Net Revenue Retention Calculator: Free net revenue retention calculator. Enter starting MRR, expansion, contraction and churn to get NRR and GRR percent in your browser.
Operating Margin Calculator: Free operating margin calculator. Enter revenue, cost of goods and operating expenses to get operating income and margin percent in your browser.
Revenue Growth Rate Calculator: Free revenue growth rate calculator. Compare two periods to get percent growth and the absolute change in revenue instantly in your browser.

Cooking

Air Fryer Conversion Calculator: Free air fryer conversion calculator. Convert conventional oven temperature and time to air fryer settings by lowering the temp and shortening the time.
Baker Hydration Percentage Calculator: Free baker hydration calculator. Compute dough hydration percentage from flour and water weights, or solve for the water needed to hit a target.
Baking Pan Size Converter: Free baking pan size converter. Adjust a recipe for a different pan by comparing pan area and volume, so you scale batter to avoid over or underfilling.
Bread Water Temperature Calculator: Free bread water temperature calculator. Find the water temperature to hit a target dough temperature using flour temp, room temp, and friction.
Brine Ratio Calculator: Free brine ratio calculator. Get the salt and water for a wet brine at a chosen concentration, so poultry and pork come out juicy and seasoned.
Butter Converter: Free butter converter. Convert butter between US sticks, tablespoons, cups, grams, and ounces instantly, using standard stick weights for recipes.
Calories Per Serving Calculator: Free calories per serving calculator. Add up the calories of every recipe ingredient and divide by servings to get calories per portion instantly.
Cocktail Ratio Calculator: Free cocktail ratio calculator. Scale a spirit to sweet to sour ratio to any drink volume or number of servings, in ounces or milliliters.
Coffee to Water Ratio Calculator: Free coffee to water ratio calculator. Enter your brew ratio and cups to get exact grams of coffee and water for pour over, French press, and drip.
Cups to Grams Converter: Free cups to grams converter. Convert cups to grams by ingredient using common baking densities for flour, sugar, butter, and more, live as you type.
Egg Size Substitution Calculator: Free egg size substitution calculator. Convert a recipe between small, medium, large, and extra-large eggs by liquid volume so ratios stay correct.
Grill Temperature Doneness Guide: Free grill doneness guide. Look up safe and target internal temperatures for beef, chicken, pork, fish, and burgers in Celsius and Fahrenheit.
Ingredient Substitution Finder: Free ingredient substitution finder. Search a common ingredient and get proven kitchen substitutes with the right amounts for baking and cooking.
Meat Roasting Time Calculator: Free meat roasting time calculator. Estimate oven roasting time by weight and doneness for beef, pork, and lamb, with target internal temperatures.
Oven Temperature Converter: Free oven temperature converter. Convert between Celsius, Fahrenheit, gas mark, and fan (convection) oven settings instantly as you type.
Recipe Scaler: Free recipe scaler. Multiply or divide any recipe by a factor or by target servings and it rescales every ingredient line automatically.
Slow Cooker Time Converter: Free slow cooker time converter. Convert conventional oven or stovetop cooking time to slow cooker low and high settings for stews, roasts, and soups.
Sourdough Starter Feeding Calculator: Free sourdough starter calculator. Work out feeding amounts from a ratio like 1:2:2 and starter weight, giving grams of starter, flour, and water.
Turkey Cooking Time Calculator: Free turkey cooking time calculator. Get roasting time and thaw time by turkey weight for a stuffed or unstuffed bird, with a safe internal temperature.
Yeast Converter: Free yeast converter. Convert between active dry, instant, and fresh (cake) yeast by weight using standard baking ratios, updating live as you type.

Home & Real Estate

Cap Rate Calculator: Free cap rate calculator for real estate. Enter net operating income and property price to find the capitalization rate on an investment.
Closing Cost Estimator: Free closing cost estimator. Enter the home price and a closing cost percentage to estimate what a buyer pays at closing plus cash needed.
Concrete Slab Calculator: Free concrete slab calculator. Enter slab length, width and thickness to find cubic yards of concrete and 80 lb bags needed.
Deck Board Calculator: Free deck board calculator. Enter deck size and board dimensions to estimate how many deck boards and linear feet you need to build a deck.
Drywall Sheet Calculator: Free drywall calculator. Enter wall and ceiling area plus sheet size to estimate how many sheets of drywall you need for a room.
Flooring Calculator: Free flooring calculator. Enter room length and width plus a waste factor to find total square footage and boxes of flooring to buy.
Grass Seed Calculator: Free grass seed calculator. Enter lawn size and seeding rate to find how many pounds of grass seed you need for a new or overseeded lawn.
Gravel Calculator: Free gravel calculator. Enter area length, width and depth to find cubic yards and tons of gravel for a driveway or path.
Home Affordability Calculator: Free home affordability calculator. Enter income, debts, down payment and rate to estimate the home price you can afford to buy.
Lawn Fertilizer Calculator: Free lawn fertilizer calculator. Enter lawn size, target nitrogen rate and the bag N number to find pounds of fertilizer to apply.
Mulch Calculator: Free mulch calculator. Enter bed length, width and depth to find cubic yards of mulch and how many bags you need for landscaping.
Paint Calculator: Free paint calculator. Enter wall length, height, doors and windows to estimate gallons of paint needed per coat for any room.
Plants Per Square Foot Calculator: Free plant spacing calculator. Enter bed size and plant spacing to find how many plants you need to fill a garden bed or ground cover area.
Price Per Square Foot Calculator: Free price per square foot calculator. Enter a home price and its size to find the cost per square foot and compare listings fairly.
Property Tax Calculator: Free property tax calculator. Enter home value and the tax rate or mill rate to estimate your annual and monthly property tax bill.
Rent Affordability Calculator: Free rent affordability calculator. Enter your income and debts to find the monthly rent you can comfortably afford using the 30 percent rule.
Rental Yield Calculator: Free rental yield calculator. Enter monthly rent, property price and costs to find gross and net rental yield on an investment property.
Roof Pitch Calculator: Free roof pitch calculator. Enter rise and run to find roof slope, angle in degrees and the rafter length multiplier for a roof.
Room Area Calculator: Free room area calculator. Enter length and width to find square footage, and add multiple rooms to get a running total for a whole project.
Room BTU Calculator: Free room BTU calculator. Enter room size, ceiling height and sun exposure to estimate the BTU rating you need for heating or cooling.
Stair Stringer Calculator: Free stair calculator. Enter total rise and run to find the number of steps, riser height and tread depth for a code friendly staircase.
Tile Calculator: Free tile calculator. Enter area size and tile dimensions to find how many tiles and boxes you need including a waste allowance.
Topsoil Calculator: Free topsoil calculator. Enter area length, width and depth to find cubic yards and bags of topsoil for a garden or lawn.
Wallpaper Calculator: Free wallpaper calculator. Enter wall length, height and roll size to estimate how many rolls of wallpaper you need for a room.

Automotive

Car Depreciation Calculator: Estimate how much value a car loses each year. See year by year value from purchase price and an annual depreciation rate.
Car Lease vs Buy Calculator: Compare leasing and buying a car over the same period. See total cost, monthly payment, and the equity you keep by buying.
Cost Per Mile Calculator: Calculate the true cost per mile of driving from fuel, insurance, maintenance, and depreciation over your yearly mileage.
Engine Displacement Calculator: Calculate engine displacement from bore, stroke, and cylinder count. Get the result in cc, liters, and cubic inches at once.
EV Charging Cost Calculator: Calculate the cost to charge an electric car from battery size, charge level, charging losses, and your electricity price per kWh.
EV Charging Time Calculator: Estimate how long it takes to charge an electric car from battery size, charger power, and the charge percentage you need.
EV vs Gas Cost Calculator: Compare the fuel cost of an electric car and a gas car per mile and per year, and see how much you would save by going electric.
Fuel Cost Calculator: Calculate the fuel cost of any trip from distance, fuel economy, and gas price. Works in MPG or L/100km with instant results.
Fuel Savings Calculator: Compare two cars by fuel economy and see the yearly and 5 year fuel savings you get from switching to the more efficient one.
Gear Ratio Calculator: Calculate final drive gear ratio from ring and pinion teeth, plus engine RPM at a given speed for your tire size and gearing.
Horsepower Torque RPM Calculator: Solve horsepower, torque, or RPM when you know the other two. Uses the classic HP equals torque times RPM over 5252 formula.
L/100km Calculator: Calculate fuel consumption in liters per 100 km from distance and liters used. See the km per liter and MPG equivalent too.
Miles Per Tank Calculator: Calculate how far you can drive on a full tank from your tank size and MPG, plus a safe range that keeps a fuel reserve in the tank.
MPG Calculator: Calculate your real miles per gallon from miles driven and gallons used. See the L/100km equivalent and cost per mile too.
MPG to L/100km Converter: Convert miles per gallon to liters per 100 km and back. Supports both US and Imperial (UK) gallons with the exact formula.
Oil Change Cost Calculator: Estimate the yearly cost of oil changes and the cost per mile from your interval, mileage, oil, filter, and labor prices.
Road Trip Fuel Calculator: Plan a road trip budget: enter distance, fuel economy, price, and passengers to see total fuel cost and cost per person.
Speedometer Error Calculator: Calculate speedometer error after a tire size change. Enter old and new tire diameters to see your true speed at any indicated reading.
Tire Size Calculator: Read a tire size code like 225/45R17 and get the overall diameter, sidewall height, circumference, and revolutions per mile.
Tire Size Comparison Calculator: Compare two tire sizes and see the difference in diameter, sidewall, and how much your speedometer reads off with the new size.
US MPG to Imperial MPG Converter: Convert US MPG to UK Imperial MPG and back. Imperial gallons are larger, so the same car reads higher in UK MPG figures.
Wheel Offset Calculator: Compare wheel offsets and see how far a new wheel moves in or out. Enter width and offset to find the change at the fender and hub.
Zero to Sixty Estimator: Estimate a car 0 to 60 mph time from horsepower and weight using a power to weight model. See the power to weight ratio too.

Geometry

3D Distance Calculator: Free 3D distance calculator. Enter two points in x y z space to get the straight line distance between them instantly using the 3D distance formula.
Arc Length Calculator: Free arc length calculator. Enter the radius and central angle to get the arc length of a circle using r times theta, instantly in your browser.
Circle Area Calculator: Free circle area calculator. Enter a radius or diameter to get the area of a circle instantly using pi times r squared, right in your browser.
Circle Circumference Calculator: Free circle circumference calculator. Enter a radius or diameter to get the distance around a circle using 2 pi r, instantly in your browser.
Cone Volume Calculator: Free cone volume calculator. Enter the radius and height to get the volume, slant height and surface area of a cone instantly in your browser.
Cube Volume Calculator: Free cube volume calculator. Enter the edge length to get the volume, surface area and diagonal of a cube instantly using edge cubed in your browser.
Cylinder Volume Calculator: Free cylinder volume calculator. Enter the radius and height to get the volume and surface area of a cylinder instantly using pi r squared h.
Ellipse Area Calculator: Free ellipse area calculator. Enter the semi major and semi minor axes to get the area of an ellipse instantly using pi times a times b.
Heron Formula Calculator: Free Heron formula calculator. Enter the three side lengths of a triangle to get its area using Heron formula instantly in your browser.
Hexagon Calculator: Free regular hexagon calculator. Enter the side length to get area, perimeter, and both the long and short diagonals of a hexagon instantly.
Parallelogram Area Calculator: Free parallelogram area calculator. Enter the base and height to get the area of a parallelogram instantly using base times height in your browser.
Pyramid Volume Calculator: Free square pyramid volume calculator. Enter the base edge and height to get the volume, slant height and surface area of a pyramid in your browser.
Pythagorean Theorem Calculator: Free Pythagorean theorem calculator. Enter two sides of a right triangle to find the hypotenuse or a missing leg using a squared plus b squared.
Rectangle Area Calculator: Free rectangle area calculator. Enter length and width to get the area and perimeter of a rectangle instantly, all in your browser.
Rectangular Prism Volume Calculator: Free rectangular prism volume calculator. Enter length, width and height to get the volume and surface area of a box instantly in your browser.
Regular Polygon Area Calculator: Free regular polygon area calculator. Enter the number of sides and side length to get area and perimeter of any regular polygon in your browser.
Rhombus Area Calculator: Free rhombus area calculator. Enter the two diagonals to get the area of a rhombus instantly using half the product of the diagonals in your browser.
Right Triangle Calculator: Free right triangle calculator. Enter the two legs to get the hypotenuse, area, perimeter and both acute angles of a right triangle instantly.
Sector Area Calculator: Free circle sector area calculator. Enter the radius and central angle in degrees to get the area of a pie slice sector instantly in your browser.
Sphere Volume Calculator: Free sphere volume calculator. Enter the radius to get the volume and surface area of a sphere instantly using four thirds pi r cubed in your browser.
Square Area Calculator: Free square area calculator. Enter the side length to get the area, perimeter and diagonal of a square instantly in your browser.
Surface Area of a Box Calculator: Free box surface area calculator. Enter length, width and height to get the total surface area of a rectangular box instantly in your browser.
Trapezoid Area Calculator: Free trapezoid area calculator. Enter the two parallel sides and the height to get the area of a trapezoid instantly in your browser.
Triangle Perimeter Calculator: Free triangle perimeter calculator. Enter the three side lengths to get the perimeter and semi perimeter of a triangle instantly in your browser.

Music

BPM Tap Counter: Free BPM tap tempo tool. Tap a key or button in time with any song and read the tempo in beats per minute instantly in your browser.
BPM to Hz Converter: Free BPM to Hz converter. Turn a tempo in beats per minute into a frequency in hertz for setting LFOs, tremolo and modulation to the beat.
Cents Calculator: Free cents calculator. Convert a frequency ratio or two pitches into cents, the fine pitch unit where one hundred cents equals a semitone.
Chord Note Finder: Free chord note finder. Pick a root note and chord quality like major, minor or dominant seventh to see the exact notes that make up the chord.
Delay Time Calculator: Free delay and reverb time calculator. Enter a tempo in BPM and get delay times in milliseconds and Hz for every note value from whole to sixteenth.
Frequency to Note Converter: Free frequency to note converter. Enter any pitch in Hz and get the closest musical note, octave and how many cents sharp or flat it sits.
Key Transpose Calculator: Free key transpose calculator. Enter a musical key and a number of semitones to instantly get the new transposed key, up or down.
MIDI Note Number Calculator: Free MIDI note number calculator. Convert between MIDI note numbers, note names and frequency in Hz where middle C is MIDI 60 and A4 is 69.
Note Frequency Calculator: Free note to frequency calculator. Pick a note name and octave to see its exact pitch in Hz using equal temperament with A4 tuned to 440 Hz.
Note Interval Calculator: Free musical interval calculator. Pick two notes and see the interval name, the number of semitones and the frequency ratio between them.
Note Wavelength Calculator: Free note wavelength calculator. Enter a musical note or frequency to find its sound wavelength in air, useful for speaker and room acoustics.
Octave Frequency Calculator: Free octave frequency calculator. Enter a frequency and shift it up or down by whole octaves to see how the pitch doubles or halves in Hz.
Online Metronome: Free online metronome. Set any tempo and time signature and get an accurate Web Audio click track right in your browser, no download needed.
Reverb Decay Calculator: Free reverb decay time calculator. Enter a tempo in BPM to get tempo synced reverb decay and pre delay times in milliseconds for tight mixes.
Sample Rate and Bit Depth Reference: Free audio sample rate reference. Compare 44.1 kHz, 48 kHz and higher rates, learn the Nyquist limit, and estimate uncompressed file size per minute.
Scale Note Finder: Free scale note finder. Choose a key and a mode or scale type like major, minor or dorian to list all the notes in the scale instantly.
Semitone Frequency Calculator: Free semitone frequency calculator. Enter a starting frequency and a number of semitones to see the resulting pitch in Hz using 12-TET math.
Song Length Calculator: Free song length calculator. Enter tempo, bars and time signature to work out how long a section or full track runs in minutes and seconds.
Tempo Marking Reference: Free tempo marking reference. Look up Italian tempo terms like largo, andante and allegro with their beats per minute ranges, or find the term for a BPM.
Time Signature Reference: Free time signature reference. Learn what the top and bottom numbers mean, simple versus compound meter, and common signatures with beat groupings.

Writing

Adverb Counter: Free adverb counter. Highlight -ly adverbs and see what share of your writing they make up, computed instantly in your browser.
Automated Readability Index Calculator: Free Automated Readability Index calculator. Get a US grade level from characters, words and sentences instantly in your browser.
Average Word Length Calculator: Free average word length calculator. Measure mean characters per word and syllables per word to gauge how dense your writing is.
Cliche Finder: Free cliche finder. Detect tired phrases like at the end of the day and think outside the box so you can freshen up your writing.
Coleman-Liau Index Calculator: Free Coleman-Liau index calculator. Get a US grade level from letters and sentences per hundred words, no syllable counting, in your browser.
Dialogue Percentage Calculator: Free dialogue percentage calculator. Measure how much of your story is spoken dialogue versus narration, computed in your browser.
Filler Word Finder: Free filler word finder. Spot padding words like just, really, very and actually so you can cut them, all in your browser.
Flesch-Kincaid Grade Level Calculator: Free Flesch-Kincaid grade level calculator. Find the US school grade needed to read your text, computed instantly in your browser.
Gunning Fog Index Calculator: Free Gunning Fog index calculator. Measure text complexity by grade level using sentence length and complex words, all in your browser.
Lexical Diversity Calculator: Free lexical diversity calculator. Measure vocabulary richness with the type token ratio and root TTR instantly in your browser.
Longest Words Finder: Free longest words finder. Rank the longest words in your text by character count so you can simplify dense vocabulary, in your browser.
Passive Voice Detector: Free passive voice detector. Find passive sentences and get the passive share of your text instantly in your browser, no upload needed.
Readability Score Calculator: Free readability score calculator. Get the Flesch Reading Ease score and grade level for any text instantly in your browser, no sign up.
Repeated Word Finder: Free repeated word finder. Detect words you overuse and catch adjacent duplicate words in your writing, all in your browser.
Sentence Length Analyzer: Free sentence length analyzer. See average, longest and shortest sentence lengths and flag overly long sentences, all in your browser.
SMOG Index Calculator: Free SMOG index calculator. Estimate reading grade from polysyllable counts, the standard for health and medical readability, in your browser.
Speaking Time Calculator: Free speaking time calculator. Estimate how long your speech or script takes to read aloud at your chosen pace, computed in your browser.
Syllable Counter: Free syllable counter. Count syllables in a word, phrase or full text using an English heuristic, computed instantly in your browser.
Text Complexity Analyzer: Free text complexity analyzer. Combine multiple readability formulas into one consensus grade and complexity snapshot, in your browser.
Transition Word Counter: Free transition word counter. Measure how many sentences use transition words like however and therefore to improve flow, in your browser.
Unique Word Counter: Free unique word counter. Count distinct words versus total and see your repetition rate instantly in your browser, no upload needed.
Weasel Word Finder: Free weasel word finder. Catch vague qualifiers like some, many, arguably and reportedly that weaken claims, all in your browser.

Statistics

Binomial Probability Calculator: Free binomial probability calculator. Enter trials, successes and success probability to find exact, at most and at least binomial probabilities.
Coefficient of Variation Calculator: Free coefficient of variation calculator. Paste a data set to find the CV, the standard deviation as a percent of the mean, for comparing spread.
Confidence Interval Calculator: Free confidence interval calculator. Enter a sample mean, standard deviation and size to get the lower and upper bounds at 90, 95 or 99 percent.
Correlation Coefficient Calculator: Free Pearson correlation coefficient calculator. Paste paired x and y data to find r, the strength and direction of a linear relationship.
Covariance Calculator: Free covariance calculator. Paste paired x and y data to find the sample and population covariance measuring how two variables vary together.
Five Number Summary Calculator: Free five number summary calculator. Paste a data set to get the minimum, first quartile, median, third quartile and maximum at a glance.
Geometric Mean Calculator: Free geometric mean calculator. Paste positive numbers to find their geometric mean, the right average for growth rates, ratios and returns.
Harmonic Mean Calculator: Free harmonic mean calculator. Paste positive numbers to find their harmonic mean, the correct average for rates like speed and price ratios.
Interquartile Range Calculator: Free interquartile range calculator. Paste a data set to find the IQR along with the first and third quartiles and the median in one step.
Margin of Error Calculator: Free margin of error calculator. Enter a sample proportion, sample size and confidence level to find the plus or minus error of your poll.
Normal Distribution Calculator: Free normal distribution calculator. Enter a value, mean and standard deviation to find the probability density and cumulative probability.
Outlier Detector (1.5 IQR): Free outlier detector using the 1.5 IQR rule. Paste a data set to find outliers, the fence boundaries and the clean values that remain.
P-Value from Z-Score Calculator: Free p-value calculator from a z-score. Enter a z value and choose a one or two tailed test to get the exact p-value for hypothesis testing.
Percentile Calculator: Free percentile calculator. Paste a data set and pick a percentile from 0 to 100 to find the value at that position using linear interpolation.
Percentile Rank Calculator: Free percentile rank calculator. Paste a data set and a value to find what percent of the numbers fall at or below it, from 0 to 100.
Poisson Probability Calculator: Free Poisson probability calculator. Enter an average rate and a count to find exact, at most and at least Poisson probabilities for rare events.
Relative Frequency Calculator: Free relative frequency calculator. Paste category counts to build a frequency table with relative and cumulative frequencies as percentages.
Sample Size Calculator: Free sample size calculator for surveys. Enter your confidence level, margin of error and population to find how many responses you need.
Standard Error of the Mean Calculator: Free standard error calculator. Paste a data set or enter a standard deviation and sample size to find the standard error of the mean.
Variance Calculator: Free variance calculator. Paste a data set to find the sample and population variance, plus standard deviation, mean and sum of squares.
Weighted Mean Calculator: Free weighted mean calculator. Enter values and their weights to find the weighted average, where more important items count for more.
Z-Score Calculator: Free z-score calculator. Enter a value, mean and standard deviation to find how many standard deviations it sits from the average, with percentile.

Gaming

Aim Reaction Benchmark: Test your reaction time by clicking the moment the box turns green. Get your best, average and a gamer rating over five tries in your browser.
APM Calculator: Calculate actions per minute (APM) from total actions and match duration. Measure your speed in RTS and strategy games privately in your browser.
Chess Rating Change Calculator: Estimate your chess rating change across a tournament from your rating, opponents and results. Uses expected score math, private in your browser.
cm/360 Calculator: Calculate cm/360, the mouse distance for a full turn, from DPI, sensitivity and game yaw. Dial in your aim distance instantly in your browser.
Controller Deadzone Calculator: Calculate the effective usable stick range after a controller deadzone and see remapped output at any raw input. Runs privately in your browser.
DPS Calculator: Calculate damage per second from hit damage, fire rate, crit chance and crit multiplier. Compare weapon builds instantly and privately in your browser.
eDPI Calculator: Calculate your eDPI (effective DPI) from mouse DPI and in game sensitivity. Compare true aim speed across setups instantly in your browser.
Elo Rating Calculator: Calculate new Elo ratings after a match from both player ratings, the result and a K factor. See rating change and expected score in your browser.
FPS to Frame Time Calculator: Convert FPS to frame time in milliseconds and back. See how many ms each frame takes and the frametime budget for smooth gameplay.
Gacha Pity Calculator: Track how many gacha pulls until pity and the currency needed. Enter pity count, current pulls and cost to plan your next banner in your browser.
Gacha Pull Probability Calculator: Calculate the chance of pulling at least one target unit over N gacha pulls. Uses correct at least one probability math, private in your browser.
Game FOV Converter: Convert field of view between horizontal, vertical and aspect ratios. Match FOV across games and monitors instantly in your browser.
Game Resolution Scaler: Calculate render resolution from a resolution scale percentage, plus total pixels and pixel count change. Tune performance instantly in your browser.
Headshot Percentage Calculator: Calculate your headshot percentage from headshots and total kills. Track aim precision across sessions instantly and privately in your browser.
K/D Ratio Calculator: Calculate your kill death ratio from total kills and deaths. See your K/D and how many kills you need to reach a target instantly in your browser.
KDA Calculator: Calculate KDA (kills plus assists divided by deaths) for MOBA and shooter games. See your KDA score instantly in your browser.
Loot Drop Probability Calculator: Calculate the chance of getting a rare drop at least once over N kills or runs. Correct probability math, runs privately in your browser.
Mouse Sensitivity Converter: Convert mouse sensitivity between games using cm/360 and DPI. Match your aim across CS2, Valorant, Apex and more instantly in your browser.
Steam Sale Price Calculator: Calculate the final price of a game after a Steam style discount, plus your total savings and cost for a bundle of titles. Private in your browser.
Tickrate Reference and Calculator: Look up server tickrate values and convert tickrate to milliseconds per tick. See how tick timing affects hit registration, private in your browser.
Win Rate Calculator: Calculate your win rate from wins and losses, and see how many games you must win to hit a target percentage. Fast and private in your browser.
XP to Level Calculator: Calculate total XP needed to reach a target level and how much you still need. Supports linear and scaling curves, private in your browser.

Sports

40 Yard Dash Speed Calculator: Free 40 yard dash speed calculator. Convert a forty time into average miles per hour and kilometers per hour to see your sprint speed.
Barbell Plate Loading Calculator: Free barbell plate calculator. Enter a target weight and bar weight to see exactly which plates to load on each side of the bar.
Baseball ERA Calculator: Free baseball ERA calculator. Enter earned runs and innings pitched to get a pitcher earned run average using the standard nine inning formula.
Basketball Shooting Percentage Calculator: Free basketball shooting calculator. Get field goal, three point, free throw, effective and true shooting percentages from your makes and attempts.
Batting Average Calculator: Free baseball batting average calculator. Divide hits by at bats to get a three digit average, plus a quick read on where it ranks.
Bowling Score Calculator: Free ten pin bowling score calculator. Enter your rolls frame by frame and get a running score with correct strike and spare bonuses.
Cycling Power to Weight Calculator: Free cycling power to weight calculator. Divide your FTP by body weight to get watts per kilogram and see your rider category.
Darts Checkout Calculator: Free darts checkout calculator. Enter your remaining score in 501 and see a valid three dart finish that ends correctly on a double.
DOTS Score Calculator: Free DOTS score calculator for powerlifting. Enter bodyweight and total to get a DOTS coefficient score, the modern replacement for Wilks.
Fantasy Football Points Calculator: Free fantasy football points calculator. Enter yards, touchdowns and turnovers to score a player in standard, half PPR or full PPR.
Golf Handicap Calculator: Free golf handicap index calculator. Enter your recent score differentials and get your handicap index using the World Handicap System average method.
Golf Score Differential Calculator: Free golf score differential calculator. Turn an adjusted gross score, course rating and slope into a WHS differential in one click.
Marathon Split Calculator: Free marathon split calculator. Enter a goal finish time to get even and negative split pacing for every 5K and the half marathon mark.
NFL Passer Rating Calculator: Free NFL passer rating calculator. Enter completions, attempts, yards, touchdowns and interceptions for the official quarterback rating.
On Base Percentage Calculator: Free OBP calculator for baseball. Enter hits, walks, hit by pitch and plate appearances to get on base percentage the correct way.
OPS Calculator: Free baseball OPS calculator. Add on base percentage and slugging percentage to get OPS, the popular all in one offensive rating.
Points Per Game Calculator: Free points per game calculator. Divide total points by games played to get a per game scoring average for any sport, plus a season projection.
Race Split Time Calculator: Free race split time calculator. Enter a target finish time and race distance to get an even pace and the clock time at every split.
Slugging Percentage Calculator: Free slugging percentage calculator. Enter singles, doubles, triples and home runs against at bats to get SLG and total bases.
Swimming Pace Calculator: Free swimming pace calculator. Enter a swim time and distance to get your pace per 100 meters or 100 yards plus average speed.
Vertical Jump Power Calculator: Free vertical jump power calculator using the Sayers formula. Enter jump height and body weight to estimate peak leg power in watts.
Wilks Score Calculator: Free Wilks calculator for powerlifting. Enter bodyweight and total lifted to get a Wilks score that compares strength across weight classes.

Weather

Absolute Humidity Calculator: Free absolute humidity calculator. Enter temperature and relative humidity to find grams of water vapor per cubic meter of air.
Air Density Calculator: Free air density calculator. Enter temperature, pressure and humidity to find moist air density in kilograms per cubic meter.
Beaufort Wind Scale Reference: Free Beaufort wind scale reference. Enter a wind speed to find its Beaufort force number, name and the sea and land effects that go with it.
Cloud Base Height Calculator: Free cloud base calculator using the Espy formula. Enter surface temperature and dew point to estimate the height of cumulus cloud bases.
Density Altitude Calculator: Free density altitude calculator. Enter pressure altitude and temperature to find density altitude and gauge aircraft and engine performance loss.
Dew Point Calculator: Free dew point calculator using the Magnus-Tetens formula. Enter temperature and relative humidity to find the dew point and comfort level.
Feels Like Temperature Calculator: Free feels like temperature calculator. Combines heat index in warm weather and wind chill in cold weather to show the real apparent temperature.
Frost Point Calculator: Free frost point calculator. Enter temperature and relative humidity to find the frost point, the temperature at which frost forms on surfaces.
Growing Degree Days Calculator: Free growing degree days calculator. Enter daily high and low temperatures and a base temperature to find GDD accumulation for crop growth.
Heat Index Calculator: Free heat index calculator using the NWS Rothfusz regression. Enter air temperature and relative humidity to find how hot it really feels.
Humidex Calculator: Free humidex calculator using the Canadian formula. Enter air temperature and dew point to find the humidex and how hot it feels with humidity.
Lightning Distance Calculator: Free lightning distance calculator. Enter the seconds between a lightning flash and thunder to find how far away the storm is and if it is a threat.
Pressure Altitude Calculator: Free pressure altitude calculator. Enter field elevation and the altimeter setting to find pressure altitude for aviation performance planning.
Rainfall Volume Calculator: Free rainfall volume calculator. Enter rainfall depth and a roof or catchment area to find the total water volume collected in liters and gallons.
Relative Humidity Calculator: Free relative humidity calculator. Enter air temperature and dew point to find the relative humidity using saturation vapor pressure ratios.
Saffir-Simpson Hurricane Scale Reference: Free Saffir-Simpson hurricane scale reference. Enter sustained wind speed to find the hurricane category and its expected damage.
Snow to Water Ratio Calculator: Free snow to water ratio calculator. Convert snowfall depth to liquid water equivalent, or water to snow, using the ratio for your snow type.
UV Index Reference and Burn Time: Free UV index reference. Enter the UV index and your skin type to see the risk level, protection advice and estimated time to sunburn.
Wet Bulb Globe Temperature Calculator: Free WBGT calculator estimating outdoor wet bulb globe temperature from air temperature, humidity and sun to gauge heat stress risk zones.
Wet Bulb Temperature Calculator: Free wet bulb temperature calculator using the Stull approximation. Enter air temperature and relative humidity to find the wet bulb temperature.
Wind Chill Calculator: Free wind chill calculator using the 2001 NWS/Environment Canada formula. Enter temperature and wind speed to find the wind chill temperature.

Pets

Aquarium Volume Calculator: Free aquarium volume calculator. Find the water volume of a rectangular fish tank in litres and gallons from its length, width, and height.
Cat Calorie Calculator (RER and MER): Free cat calorie calculator. Estimate daily calories for your cat from resting energy needs and a life stage factor using the RER and MER method.
Cat Food Portion Calculator: Free cat food portion calculator. Convert your cat daily calorie needs and the food calories per can or cup into a clear daily feeding amount.
Cat Litter Usage Calculator: Free cat litter usage calculator. Estimate how much litter you use per month and the yearly cost from your number of cats and change routine.
Cat Pregnancy Due Date Calculator: Free cat pregnancy calculator. Estimate your cat queening due date and key milestones from the mating date using a 65 day feline gestation.
Dog Age by Breed Size Calculator: Free dog age calculator by breed size. Convert dog years to human years with a size adjusted model instead of the naive times seven rule.
Dog Body Condition Score Estimator: Free dog body condition score tool. Answer quick rib, waist, and belly questions to estimate a 1 to 9 body condition score and weight status.
Dog Calorie Calculator (RER and MER): Free dog calorie calculator. Work out daily calories for your dog from resting energy needs and an activity factor using the standard RER and MER method.
Dog Chocolate Toxicity Calculator: Free dog chocolate toxicity calculator. Estimate the theobromine dose from the chocolate type and amount your dog ate against common risk thresholds.
Dog Crate Size Calculator: Free dog crate size calculator. Get recommended crate length and height from your dog body measurements so it can stand, turn, and lie down.
Dog Food Portion Calculator: Free dog food portion calculator. Turn your dog daily calorie needs and the food calories per cup into a daily cup and gram feeding amount.
Dog Pregnancy Due Date Calculator: Free dog pregnancy calculator. Estimate your dog whelping due date and week by week timeline from the breeding date using a 63 day gestation.
Dog Walking Distance Calculator: Free dog walking calculator. Estimate a daily walk distance and time target for your dog based on its energy level, age band, and body weight.
Dog Water Intake Calculator: Free dog water intake calculator. Estimate how much water your dog should drink per day from its body weight using a common ml per kg guideline.
Fish Tank Stocking Calculator: Free fish tank stocking calculator. Estimate how many fish a tank can hold with the classic inch per gallon guide and a safer adjusted figure.
Horse Age to Human Years Calculator: Free horse age calculator. Convert your horse age into human years with a staged model that reflects fast early growth and slower later aging.
Pet Medication Dosing Schedule Planner: Free pet medication schedule planner. Turn a start time and dosing interval into a clear list of dose times across the next day or two.
Pet Sitting Cost Calculator: Free pet sitting cost calculator. Estimate the total price of pet sitting or boarding from the daily rate, number of days, pets, and extra visits.
Puppy Adult Weight Predictor: Free puppy adult weight predictor. Estimate how big your puppy will grow from its current age and weight using a simple growth ratio method.
Rabbit Age to Human Years Calculator: Free rabbit age calculator. Convert your rabbit age into human years with a staged model that reflects fast maturing youth and a long adult phase.

Fashion & Sizing

Belt Size Calculator: Free belt size calculator. Enter your pant waist or actual waist measurement and get the correct belt size in inches and centimeters.
Bra Size Calculator: Free bra size calculator. Enter your underbust and bust measurements to find your band and cup size using the standard inch difference method.
Bra Size Converter: Free bra size converter between US, UK, EU and French/AU sizing. Enter a band and cup and see the matching label in every regional system.
Clothing Size Converter: Free clothing size converter for men and women. Translate alpha sizes like S, M and L into US, UK and EU numeric sizes with one selection.
Dress Size Converter: Free womens dress size converter across US, UK, EU, IT and alpha sizes. Enter one dress size and see every international equivalent instantly.
Foot Length to Shoe Size: Free foot length to shoe size calculator. Measure your foot in cm or inches and get accurate US, UK and EU shoe sizes for men and women.
Glove Size Calculator: Free glove size calculator. Measure your hand circumference and get your numeric glove size plus an S to XL alpha size for men and women.
Hat Size Calculator: Free hat size calculator. Measure your head circumference in cm or inches and get your US, UK, EU and alpha hat size instantly.
International Shoe Size Converter: Free shoe size converter across US, UK, EU and centimeters for men and women. Enter one size and see every equivalent instantly in your browser.
International Size Chart Reference: Free international clothing size chart. Quick reference tables for womens and mens tops, waist and shoes across US, UK and EU sizing.
Jeans Size Calculator: Free jeans size calculator. Convert your waist and inseam measurements into US W/L jeans sizing and equivalent EU and alpha sizes.
Kids Clothing Size by Age: Free kids clothing size chart by age. Enter a child age to see the typical US, UK and EU clothing size plus average height and weight.
Kids Shoe Size by Age: Free kids shoe size chart by age. Enter a child age to see the typical US, UK and EU shoe size and the matching foot length in cm.
Men's Shirt Size Calculator: Free mens dress shirt size calculator. Enter your neck and sleeve measurements to get the correct collar size and sleeve length fit.
Necklace Length Guide: Free necklace length guide. Enter a chain length in inches or centimeters and see where it sits and the traditional style name.
Ring Size Converter: Free ring size converter across US, UK, EU, diameter and circumference. Enter one and see every equivalent ring size measurement instantly.
Ring Size from Circumference: Free ring sizer. Wrap a strip of paper around your finger, enter the circumference or diameter, and get your US, UK and EU ring size.
Sock Size Converter: Free sock size converter. Turn your US shoe size into the numeric sock size and an S to XL alpha size for men and women.
Suit Jacket Size Calculator: Free suit jacket size calculator. Enter your chest measurement and height to get your jacket size and short, regular or long length.
Waist to Pant Size Converter: Free waist to pant size converter. Turn a waist measurement into US, UK and EU pant sizes and an S to XL alpha size for men and women.
Watch Band Size Calculator: Free watch band size calculator. Enter your wrist circumference to find the recommended strap length and typical S, M or L band size.

Photography

Bellows Extension Factor Calculator: Calculate the exposure compensation in stops for macro and bellows extension from focal length and total lens extension. Fix dark macro shots.
Color Temperature and White Balance Reference: Look up the color temperature in Kelvin for common light sources and match the right white balance preset for accurate photo colors.
Crop Factor Calculator: Convert a lens focal length to its full frame equivalent using your camera crop factor. Compare APS-C, Micro Four Thirds, and more.
Depth of Field Calculator: Calculate the depth of field for any lens from focal length, aperture, subject distance, and sensor size. See near, far, and total sharp zone.
Diffraction Limit Calculator: Find the aperture where diffraction starts to soften your images based on sensor and pixel size. Know the sharpest f-stop to use.
Equivalent Aperture Calculator: Convert an aperture to its full frame equivalent for depth of field and light gathering across sensor sizes. Compare lenses fairly.
Exposure Value (EV) Calculator: Calculate the exposure value from aperture, shutter speed, and ISO. Convert between EV, light value, and camera settings for any scene.
Field of View Calculator: Calculate the angle of view of any lens from focal length and sensor size. See horizontal, vertical, and diagonal field of view in degrees.
Flash Guide Number Calculator: Calculate flash aperture, distance, or guide number for correct exposure. Solve any of the three from the other two in meters or feet.
Golden Hour and Blue Hour Guide: Learn when golden hour and blue hour happen relative to sunrise and sunset, with a planner that estimates the windows from your sun times.
Hyperfocal Distance Calculator: Find the hyperfocal distance for any lens and aperture. Focus there to keep everything from half that distance to infinity acceptably sharp.
ISO Invariance and Noise Reference: Understand ISO invariance, when to raise ISO versus brighten in post, and how ISO, noise, and dynamic range interact on modern sensors.
Megapixel to Print Size Calculator: See the largest print size your camera megapixels support at 150, 200, and 300 DPI. Turn a megapixel count into real print dimensions.
Motion Blur Shutter Speed Calculator: Find the shutter speed to freeze or intentionally blur a moving subject from its speed, distance, and direction across the frame.
ND Filter Calculator: Calculate the new shutter speed after adding a neutral density filter. Enter base shutter and ND stops to get long exposure times.
Photo File Size Estimator: Estimate RAW and uncompressed image file size from megapixels and bit depth, plus JPEG sizes and how many fit on a memory card.
Print Size and DPI Calculator: Find the largest quality print size from your image pixels and target DPI, or the DPI you get at a chosen print size. Inches and cm.
Reciprocal Shutter Rule Calculator: Find the slowest handheld shutter speed that avoids blur using the reciprocal rule from focal length, sensor, and image stabilization.
Star Photography 500 Rule Calculator: Find the longest shutter speed before stars blur using the 500 and NPF rules from focal length and sensor. Sharp astrophotography.
Stops of Light Calculator: Convert changes in aperture, shutter speed, or ISO into stops of light and back. Understand equivalent exposures and stop differences.
Sunny 16 Rule Calculator: Apply the Sunny 16 rule to find shutter speed and aperture for any lighting from your ISO. Meter-free daylight exposure made simple.
Time Lapse Calculator: Plan a time lapse: find clip length, frame count, interval, or shooting time from the others. Includes storage size and card estimate.

Astronomy

Absolute Magnitude Calculator: Free absolute magnitude calculator. Convert between apparent and absolute magnitude using the distance modulus, and solve for distance in parsecs and light years.
Angular Size Calculator: Free angular size calculator. Find how large an object appears in the sky in degrees, arcminutes and arcseconds from its true diameter and distance, or solve for size.
CCD Pixel Scale Calculator: Free CCD pixel scale calculator for astrophotography. Find arcseconds per pixel from your camera pixel size and telescope focal length to check if you are matched to seeing.
Escape Velocity Calculator: Free escape velocity calculator. Find the speed needed to escape a planet, moon or star from its mass and radius using the square root of two GM over r.
Kepler Third Law Calculator: Free Kepler third law calculator for the solar system. Convert between orbital period in years and semi-major axis in astronomical units where P squared equals a cubed.
Light Travel Time Calculator: Free light travel time calculator. Find how long light takes to cross a distance and convert light years, light minutes and light seconds into kilometers and miles.
Orbital Period Calculator: Free orbital period calculator. Find how long a satellite or moon takes to orbit a body from the central mass and orbit radius using Newton form of Kepler third law.
Parsec to Light Year Converter: Free parsec to light year converter. Convert between parsecs, light years, astronomical units and kilometers for astronomical distances, both directions instantly.
Planet Orbital Speed Calculator: Free planet orbital speed calculator. Find how fast a planet moves around the Sun from its orbital radius using the vis-viva circular speed formula, in km/s and mph.
Redshift Velocity Calculator: Free redshift velocity calculator. Convert a spectral redshift z into recession velocity using both the simple Doppler and relativistic formulas, in km/s and fraction of light.
Schwarzschild Radius Calculator: Free Schwarzschild radius calculator. Find the event horizon size of a black hole from its mass using two GM over c squared, in meters, kilometers and solar masses.
Star Brightness Ratio Calculator: Free star brightness ratio calculator. Convert a magnitude difference between two stars into how many times brighter one is using the Pogson ratio of 2.512.
Stellar Luminosity Calculator: Free stellar luminosity calculator. Find a star total energy output from its radius and surface temperature with the Stefan-Boltzmann law, in watts and solar luminosities.
Surface Gravity Calculator: Free surface gravity calculator. Find the gravitational acceleration at the surface of a planet, moon or star from its mass and radius using g equals GM over r squared.
Telescope Exit Pupil Calculator: Free telescope exit pupil calculator. Find the exit pupil in millimeters from aperture and magnification, or from eyepiece focal length and focal ratio, to match your eye.
Telescope Focal Ratio Calculator: Free telescope focal ratio calculator. Find the f-number of a telescope from focal length and aperture, or solve for the focal length needed to hit a target f-ratio.
Telescope Limiting Magnitude Calculator: Free limiting magnitude calculator. Estimate the faintest star your telescope can show from its aperture, so you know what deep sky targets are within reach.
Telescope Magnification Calculator: Free telescope magnification calculator. Divide telescope focal length by eyepiece focal length to find power, plus your maximum useful magnification from aperture.
Telescope Resolving Power Calculator: Free telescope resolving power calculator. Find the Dawes and Rayleigh limits in arcseconds from your aperture to judge the finest double star split your scope can show.
Wien Law Peak Wavelength Calculator: Free Wien law calculator. Find the peak emission wavelength of a star or blackbody from its temperature, and see the color band it falls in, using the displacement law.

Baby & Pregnancy

Adjusted Age Calculator for Preemies: Free corrected age calculator for premature babies. Enter birth date and weeks early to find your preemie adjusted age used for tracking milestones and growth.
Baby Clothing Size by Weight: Free baby clothing size finder by weight and length. Enter your baby weight and height to see the matching newborn, 0-3, 3-6 and 6-9 month clothing size.
Baby Eye Color Predictor: Free baby eye color predictor. Enter both parents eye colors to see estimated odds your baby will have brown, blue or green eyes based on simplified genetics.
Baby Feeding Amount Calculator: Free baby feeding amount calculator. Estimate how many ounces of formula or milk your baby needs per feeding and per day based on weight and age.
Baby Food Introduction Age Guide: Free baby food introduction guide. Enter your baby age in months to see which first foods and textures are commonly introduced at each stage of starting solids.
Baby Formula Mixing Calculator: Free baby formula mixing calculator. Work out how many scoops of powder and how much water you need for a target bottle size at the standard 1 scoop per 2 ounces ratio.
Baby Head Circumference Percentile Calculator: Free baby head circumference percentile calculator using WHO growth standards. Enter age, sex and head circumference to see the head-circumference-for-age percentile.
Baby Height Percentile Calculator: Free baby length and height percentile calculator using WHO growth standards. Enter age, sex and length to see your infant length-for-age percentile up to 24 months.
Baby Kick Counter: Free baby kick counter. Tap each time you feel your baby move and time how long it takes to reach ten kicks, a common fetal movement tracking method.
Baby Shower Budget Calculator: Free baby shower budget calculator. Enter guest count and per person spend on food, decor, favors and venue to see your total baby shower cost and cost per guest.
Baby Sleep Schedule Calculator: Free baby sleep schedule calculator. Enter your baby age and wake time to see age appropriate wake windows, suggested nap times and total daily sleep.
Baby Weight Percentile Calculator: Free baby weight percentile calculator using WHO growth standards. Enter age, sex and weight to see your infant weight-for-age percentile from birth to 24 months.
Breast Milk Storage Guide: Free breast milk storage guide and calculator. See how long expressed breast milk stays safe at room temperature, in the fridge and in the freezer with dated use-by times.
Childcare Cost Calculator: Free childcare cost calculator. Estimate weekly, monthly and yearly daycare or nanny costs and see how much of your take-home pay childcare uses.
Chinese Gender Predictor: Free Chinese gender predictor based on the traditional lunar birth chart. Enter mother birth date and conception month to see the chart prediction, for fun.
Conception Date Calculator: Free conception date calculator. Estimate the likely date of conception from your last menstrual period, due date or an ultrasound based gestational age.
Contraction Timer: Free contraction timer for labor. Tap to start and stop each contraction to track duration, frequency and the interval between contractions in real time.
Diaper Cost Calculator: Free diaper cost calculator. Estimate how much you will spend on diapers per week, month and per year based on daily changes and price per diaper.
Due Date From Ultrasound Calculator: Free due date from ultrasound calculator. Enter the scan date and the measured gestational age in weeks and days to get your estimated due date and current progress.
Pregnancy Weight Gain Calculator: Free pregnancy weight gain calculator based on IOM guidelines. Enter pre-pregnancy BMI and week to see your recommended total and weekly weight gain range.

Betting & Odds

Arbitrage Betting Calculator: Free arbitrage betting calculator. Enter two opposing odds to check if a sure bet exists, then get the optimal stake split and guaranteed profit.
Betting Bankroll Management Calculator: Free bankroll management calculator for bettors. Set your bankroll and unit percentage to size flat bets and see how many units survive a losing streak.
Betting Expected Value Calculator: Free betting expected value calculator. Enter your true win probability, the odds and your stake to see the EV in dollars and whether the bet is +EV.
Betting Odds Converter: Free betting odds converter. Convert American (moneyline), decimal, fractional and implied probability odds between all four formats instantly in your browser.
Betting Unit Size Calculator: Free betting unit size calculator. Convert a bankroll and unit percentage into a dollar unit, then price any bet in units to keep staking consistent.
Break Even Win Rate Calculator: Free break even win rate calculator. Find the win percentage you need to break even at any odds, and see your ROI at a target win rate.
Each Way Bet Calculator: Free each way bet calculator. Enter fractional odds, place terms and stake to see the win and place returns of an each way horse racing or golf bet.
Hedge Bet Calculator: Free hedge bet calculator. Work out the exact stake to place on the other side to lock in a guaranteed profit or cut your loss on an open wager.
Implied Probability Calculator: Free implied probability calculator for betting odds. Turn American, decimal or fractional odds into the break even win probability the price is offering.
Kelly Criterion Calculator: Free Kelly criterion calculator. Find the optimal bet size as a percentage of your bankroll from your win probability and the decimal or American odds.
Moneyline Payout Calculator: Free moneyline payout calculator. Enter American moneyline odds and your stake to see the exact profit and total return on a winning bet.
No Vig Fair Odds Calculator: Free no vig fair odds calculator. Strip the sportsbook margin from a two way market to get each sides true fair odds and no vig win probability.
Over Under Payout Calculator: Free over under payout calculator. Enter a total, the sides odds and your stake to see if a game total goes over or under and what your bet pays.
Parlay Calculator: Free parlay calculator. Combine up to eight legs in American or decimal odds to get the total parlay odds, payout and combined win probability.
Poker Outs and Hand Odds Calculator: Free poker outs calculator. Enter your number of outs to get the odds of hitting your draw on the turn, the river and by the river in Texas Holdem.
Poker Pot Odds Calculator: Free poker pot odds calculator. Enter the pot size and the bet to call to get your pot odds as a ratio and the break even equity you need to call.
Round Robin Bet Calculator: Free round robin bet calculator. Turn your picks into every parlay combination of a chosen size, with total number of bets, cost and max payout.
Sportsbook Hold Percentage Calculator: Free hold percentage calculator. Enter both sides of a market to find the sportsbook theoretical hold, the share of every dollar wagered the book keeps.
Teaser Bet Calculator: Free teaser calculator. Move the spread or total in your favor across multiple legs, apply the teaser odds and see the adjusted lines and payout.
Vig Calculator: Free vig calculator. Enter both sides of a two way market to find the sportsbook vig, the total overround and each sides fair no vig probability.

Electronics

Ampere Hour and Watt Hour Calculator: Free amp hour calculator. Convert between ampere hours, watt hours and battery voltage, and work out energy capacity for any battery pack or cell.
Amps to Watts Calculator: Free amps to watts calculator. Enter current in amps and voltage to get the power in watts for DC and single phase AC loads, with optional power factor.
Battery Life Calculator: Free battery life calculator. Enter battery capacity in mAh and device current draw to estimate how many hours or days your battery will last before recharge.
Capacitor Energy and Charge Calculator: Free capacitor energy calculator. Enter capacitance and voltage to get the stored energy in joules and the charge in coulombs using E = half C V squared.
Capacitors in Parallel and Series Calculator: Free capacitor combination calculator. Enter capacitor values and choose series or parallel to get the total capacitance, using the correct add or reciprocal rule.
Current Divider Calculator: Free current divider calculator. Enter total current and two parallel resistors to find how the current splits between each branch using the current divider rule.
dBm to Watts Converter: Free dBm to watts converter. Convert between dBm, watts and milliwatts for RF and signal power, both directions, using the standard logarithmic relationship.
Inductive and Capacitive Reactance Calculator: Free reactance calculator. Enter frequency and an inductor or capacitor value to get the inductive or capacitive reactance in ohms for AC circuit design.
LC Resonant Frequency Calculator: Free LC resonant frequency calculator. Enter inductance and capacitance to get the resonant frequency of a tuned tank circuit using f = 1 / (2 pi sqrt(LC)).
LED Resistor Calculator: Free LED series resistor calculator. Enter supply voltage, LED forward voltage and current to get the exact resistor value, nearest E12 size and power rating.
LED Series and Parallel Array Calculator: Free LED array calculator. Design series and parallel LED strings for a given supply voltage, with per-string resistor values, total current and layout advice.
NE555 Timer Calculator: Free 555 timer calculator for astable and monostable modes. Enter resistors and capacitor to get frequency, period, duty cycle or one shot pulse width.
PCB Trace Width Calculator: Free PCB trace width calculator. Enter current, copper thickness and allowed temperature rise to get the minimum trace width for internal or external layers.
RC Time Constant Calculator: Free RC time constant calculator. Enter resistance and capacitance to get tau, the 63 percent charge time and the time to reach 5 tau or full charge.
Resistors in Parallel Calculator: Free parallel resistor calculator. Enter any number of resistor values and get the total equivalent resistance using the reciprocal parallel formula instantly.
Resistors in Series Calculator: Free series resistor calculator. Add any list of resistor values in ohms and get the total series resistance instantly, since series resistors simply add up.
Solar Panel and Battery Sizing Calculator: Free solar battery sizing calculator. Enter daily load, sun hours, system voltage and days of autonomy to size the solar array and battery bank you need.
Transformer Turns Ratio Calculator: Free transformer turns ratio calculator. Enter primary and secondary voltages or turns to get the turns ratio, output voltage and reflected current.
Voltage Drop Calculator: Free voltage drop calculator for wire runs. Enter length, current, wire cross section and material to get the voltage lost and percentage drop over the cable.
Watts to Amps Calculator: Free watts to amps calculator. Enter power in watts and voltage to get the current in amps for DC and single phase AC circuits, with power factor support.
Wire Gauge AWG Calculator: Free AWG wire gauge calculator. Convert American Wire Gauge to diameter and cross section area, or find the gauge for a diameter, with metric and imperial output.
Wire Resistance Calculator: Free wire resistance calculator. Enter length, cross section area and material to get the total resistance of a conductor using resistivity, for copper or aluminium.

Gardening

Compost Carbon to Nitrogen Ratio Calculator: Free compost C:N ratio calculator. Enter browns and greens by weight with their carbon to nitrogen ratios to blend a compost pile near the ideal 30:1 target.
Cover Crop Seed Rate Calculator: Free cover crop seed calculator. Enter your plot area and the seeding rate in pounds per acre or per 1000 sq ft to find the pounds of cover crop seed to buy.
Drip Irrigation Flow Calculator: Free drip irrigation calculator. Enter number of emitters and their flow rate to find total gallons per hour, run time for a watering goal and daily water use.
Fertilizer NPK Rate Calculator: Free fertilizer NPK calculator. Enter your bag analysis, target pounds of nitrogen per 1000 sq ft and area to find pounds of product to apply and the P and K it supplies.
Frost Free Planting Date Calculator: Free frost date planting calculator. Enter your last spring and first fall frost dates to find the safe planting window and the length of your growing season in days.
Garden Bed Soil Mix Calculator: Free garden soil mix calculator. Split a raised bed fill into compost, topsoil and aeration by percent to see the cubic feet of each ingredient for a balanced blend.
Garden Fence Material Calculator: Free garden fence calculator. Enter the perimeter of your garden and post spacing to find the number of posts, gates and total fencing length you need to buy.
Greenhouse Heater Size Calculator: Free greenhouse heating calculator. Enter greenhouse dimensions, inside and outside temperatures to find the BTU per hour and watts of heater you need to hold your target.
Grow Light Coverage Calculator: Free grow light calculator. Enter your grow area and target PPFD or watts per square foot to estimate the light wattage and coverage for seedlings and indoor plants.
Plant Watering Amount Calculator: Free plant watering calculator. Enter your garden bed area and target inches of water per week to find gallons needed and how long to run a hose or sprinkler.
Potting Soil Bag Calculator: Free potting soil calculator for containers. Enter pot size and shape and how many pots to fill to find total quarts and bags of potting mix you need.
Rain Barrel Capacity Calculator: Free rain barrel calculator. Enter your roof catchment area and rainfall to see the gallons a storm collects and how many barrels it takes to store the runoff.
Raised Bed Soil Volume Calculator: Free raised bed soil calculator. Enter bed length, width and fill depth to get the cubic feet, cubic yards and bags of soil to fill a raised garden bed.
Seed Spacing Calculator: Free seed spacing calculator. Enter bed size and the spacing between plants and rows to find how many plants fit and how many seeds to sow at your germination rate.
Seed Starting Date Calculator: Free seed starting calculator. Enter your last spring frost date and weeks to start indoors to find the exact sow date and transplant date for your seedlings.
Soil pH Amendment Calculator: Free soil pH amendment calculator. Enter current and target soil pH and bed area to estimate pounds of lime to raise pH or elemental sulfur to lower it.
Square Foot Garden Planner: Free square foot garden planner. Enter your grid of one foot squares and a crop to see plants per square and total plants for a Mel Bartholomew style raised bed.
Tree Spacing Calculator: Free tree spacing calculator. Enter your plot size and the spacing between trees and rows to find how many fruit or shade trees fit and the trees per acre.
Triangular Plant Spacing Calculator: Free triangular plant spacing calculator. Compare offset staggered planting versus square grid to fit more plants in the same bed and see the extra plants gained.
Vegetable Harvest Yield Estimator: Free vegetable yield estimator. Enter number of plants and expected yield per plant to estimate total harvest in pounds and pounds per square foot of garden bed.

Travel

Baggage Fee Calculator: Free baggage fee calculator. Add checked bags, overweight and oversize charges per direction to total your airline baggage cost for the trip.
Currency Denomination Planner: Free currency denomination planner. Enter a cash amount to see the fewest bills and coins to carry, great for withdrawing money before a trip.
Drive Time With Stops Calculator: Free drive time with stops calculator. Add driving distance, speed and rest breaks to estimate real arrival time on a long road trip.
Flight Duration Calculator: Free flight duration calculator. Estimate air time from great circle distance and cruise speed, plus taxi and climb buffer for a realistic gate time.
Frequent Flyer Mile Value Calculator: Free frequent flyer mile value calculator. Compare a cash fare to points plus fees to see cents per point and whether redeeming is worth it.
Group Trip Expense Splitter: Free group trip expense splitter. Enter who paid what, then see who owes whom and the fewest transfers to settle up. Runs in your browser.
Hotel Cost Per Night Splitter: Free hotel cost per night splitter. Enter the nightly rate, taxes, nights and guests to get each guest per-night and total room share.
Jet Lag Recovery Calculator: Free jet lag recovery calculator. Estimate how many days your body needs to adjust after crossing time zones and get direction-based tips.
Layover Time Calculator: Free layover time calculator. Enter your arrival and next departure times to see connection minutes and whether it is a safe layover.
Mileage Reimbursement Calculator: Free mileage reimbursement calculator. Multiply business miles by your per-mile rate to get the amount owed, with a round-trip option.
Packing List Generator: Free packing list generator. Pick trip length, climate and trip type to build a custom checklist you can copy, all in your browser.
Passport Photo Size Reference: Free passport photo size reference. Look up official photo dimensions in mm and inches for major countries before you take or print a photo.
Per Diem Calculator: Free per diem calculator. Enter your daily meal and lodging rates and travel days to total your business trip per diem, with a half-day rule.
Road Trip Total Cost Calculator: Free road trip total cost calculator. Combine fuel, lodging, food and tolls into one all-in trip cost and a per-person share instantly.
Schengen 90/180 Day Tracker: Free Schengen 90/180 day calculator. Enter your entry dates to see days used in the rolling 180 day window and how many stay days remain.
Time to Leave for Airport Calculator: Free time to leave for airport calculator. Work back from your flight using check-in, security and drive time to get the exact leave-by time.
Tipping by Country Reference: Free tipping by country reference. Look up customary restaurant, taxi and hotel tipping norms for popular destinations before you travel.
Travel Budget Calculator: Free travel budget calculator. Add flights, lodging, food, transport and activities to get your total trip cost and daily spend instantly.
Travel Days Countdown: Free travel days countdown. Enter your departure date to see how many days, weeks and weekends are left until your trip begins.
Travel Insurance Cost Estimator: Free travel insurance cost estimator. Enter trip cost, traveler age and trip days to estimate a rough premium range before you shop for quotes.
Trip Cost Splitter: Free trip cost splitter. Enter a total trip cost and number of travelers to see the fair per-person share instantly, all in your browser.
Walking Tour Time Estimator: Free walking tour time estimator. Enter distance, walking pace and stop time to estimate how long a self-guided walking tour will take.

Name		Name	Last commit message	Last commit date
clients		clients
.gitignore		.gitignore
LICENSE		LICENSE
README.md		README.md
catalog.json		catalog.json
openapi.json		openapi.json

Category	Tools	Browse
AI	undefined	ai
Text	undefined	text
Developer	undefined	developer
Calculators	undefined	calculators
Random & Fun	undefined	random
Converters	undefined	converters
Color	undefined	color
Generators	undefined	generators
Productivity	undefined	productivity
Image	undefined	image
PDF	undefined	pdf
Crypto	undefined	crypto
Date & Time	undefined	datetime
Data	undefined	data
SEO	undefined	seo
Social	undefined	social
Network	undefined	network
Science	undefined	science
Math	undefined	math
Finance	undefined	finance
Health & Fitness	undefined	health
Education	undefined	education
Business	undefined	business
Cooking	undefined	cooking
Home & Real Estate	undefined	home
Automotive	undefined	automotive
Geometry	undefined	geometry
Music	undefined	music
Writing	undefined	writing
Statistics	undefined	statistics
Gaming	undefined	gaming
Sports	undefined	sports
Weather	undefined	weather
Pets	undefined	pets
Fashion & Sizing	undefined	fashion
Photography	undefined	photography
Astronomy	undefined	astronomy
Baby & Pregnancy	undefined	baby
Betting & Odds	undefined	betting
Electronics	undefined	electronics
Gardening	undefined	gardening
Travel	undefined	travel

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