Most browser tools send your data to a server. These don't.
50 live browser-based utility tools for hardware diagnostics, developer parsers and encoders, text analysis and conversion, audio and acoustic testing, math and engineering calculations, security and privacy, web design and CSS, network and web references, and personal tasks.
Everything runs client-side. No uploads, no accounts.
Official Website · Blog · Changelog
| Tool | Description | Release date |
|---|---|---|
| Webcam A/V Sync & Latency Meter | Millisecond offset between webcam and microphone, OBS-ready output | 2026-05-20 |
| Gamepad & Joystick Drift Tester | Analog stick drift, dead zone visualization, button diagnostics | 2026-04-30 |
| Web MIDI Keyboard Latency Tester | Dead keys, ghost notes, and USB-to-browser MIDI input latency | 2026-04-24 |
| Mouse Polling Rate & Input Lag Tester | Browser input latency and mouse polling rate via PointerEvent API | 2026-04-24 |
| Webcam Lighting & Framing Analyzer | Lighting balance, face framing, and resolution diagnostics | 2026-04-22 |
| Dead Pixel & Flicker Test Suite | Backlight bleed, motion ghosting, and color banding checks, fullscreen test modes | 2026-04-21 |
| Live Signal Debugger (coming) | Real-time USB/Serial/Bluetooth signals from Arduino, sensors, MIDI controllers | 2026-11* |
| WebUSB Hardware Flasher (coming) | Flash firmware to ESP32, Arduino, and Raspberry Pi Pico in-browser | 2026-11* |
| Tool | Description | Release date |
|---|---|---|
| JSON Formatter, Validator & Tree Viewer | Pretty-print, minify, and browse JSON in a collapsible tree with syntax highlighting | 2026-07-10 |
| Regex Tester & Match Debugger | Live match highlighting, capture groups, and step-through debugging | 2026-07-10 |
| UUID v1, v4 & v7 Generator | Five display formats, cryptographically random, 100% local | 2026-06-28 |
| Hash Generator | MD5, SHA-1, SHA-256, SHA-512, and HMAC computation | 2026-05-20 |
| Big Log Explorer | Filter, search, and graph 500 MB+ log and JSONL files via Web Workers and IndexedDB | 2026-05-19 |
| Prompt Token Counter | Token count and context window usage for GPT-5.6, Claude Opus 5, Gemini 3.6, Kimi K3, and 33+ more models, with live daily pricing | 2026-05-19 |
| SQL Data Workbench | Query local files with SQL: Parquet, Arrow, Feather, Avro, DBF, Excel, CSV, JSON | 2026-05-15 |
| Base64 Text & File Encoder/Decoder | Converts between raw data and Base64 entirely client-side, nothing uploaded | 2026-05-06 |
| Cron Expression Parser & Next-Run Preview | Translate cron syntax into plain English, see upcoming run times at a glance | 2026-04-25 |
| JWT Decoder & Claims Inspector | Decode header and payload, check expiry and claims | 2026-04-24 |
| Text / Code Diff Viewer (coming) | Side-by-side and unified diff with line-level highlighting | 2026-10* |
| Binary Package Differ (coming) | Diff two ZIP archives or build artifacts: file tree, size delta, byte-level changes | 2026-10* |
| WASM Binary Inspector (coming) | Decompile WebAssembly to WAT, memory map, exports and imports | 2026-10* |
| Tool | Description | Release date |
|---|---|---|
| Password Entropy Analyser | Shannon entropy, zxcvbn pattern analysis, and GPU crack-time estimates | 2026-06-09 |
| URL Encoder / Decoder | Percent-encode and decode URLs and query strings with component parsing | 2026-06-06 |
| Cloud Config Sanitizer | Validate Kubernetes, Terraform, and YAML manifests, detect secrets and security smells | 2026-05-19 |
| X.509 Certificate Inspector | Validity, SANs, key algorithm, chain depth, and expiry from PEM or DER input | 2026-05-19 |
| Offline OCR & Document Redactor | Extract text and redact sensitive regions via Tesseract WASM | 2026-05-13 |
| PII Scrubber | Detect and tokenize PII, secrets, and internal data before sending to AI | 2026-05-08 |
| Browser Fingerprint & Privacy Leak Inspector | Canvas hash, WebGL renderer, audio fingerprint, fonts, and 30+ leak signals | 2026-05-04 |
| EXIF & Image Metadata Scrubber | Strip GPS coordinates, timestamps, and device data from images | 2026-04-23 |
| File Hash Verifier | SHA-256, SHA-512, SHA-1, and MD5 checksums compared against a published hash | 2026-04-23 |
| Quantum-Safe Encryptor (coming) | Post-quantum encryption and decryption via Kyber/Dilithium WASM | 2026-10* |
| Build Integrity Verifier (coming) | SHA-256 and BLAKE3 artifact comparison with functional content diff | 2026-10* |
| Local Secret Scanner (coming) | Scan code, configs, and ZIP archives for API keys, tokens, and credentials | 2026-10* |
| Tool | Description | Release date |
|---|---|---|
| Decibel & SPL Cross-Domain Calculator | Convert between dB, watts, volts, and sound pressure level, with formula reference | 2026-05-08 |
| Speaker Frequency Sweep & Resonance Tester | 20 Hz to 20 kHz sweep to find resonances, rattle points, and drop-off frequencies | 2026-04-24 |
| Microphone Quality, Noise & Latency Tester | Noise floor, clipping, frequency response, echo loopback, and round-trip latency | 2026-04-22 |
| Tool | Description | Release date |
|---|---|---|
| Aspect Ratio & Letterbox Calculator | Display resolutions and scaling for any ratio, with letterbox bars calculated automatically | 2026-05-07 |
| Ohm's Law & Power Calculator | Enter any two of voltage, current, resistance, or power, solve for the rest instantly | 2026-05-07 |
| Electrical Unit Converter | Charge, current, voltage, resistance, capacitance, inductance, and more, converted with SI precision | 2026-05-02 |
| Engineering Unit Converter | SI, imperial, and domain-specific units spanning length, mass, temperature, pressure, energy, and more | 2026-05-02 |
| Resistor Color Code Calculator | 4-band, 5-band, and 6-band decoding with tolerance, temperature coefficient, E-series | 2026-04-24 |
| Tool | Description | Release date |
|---|---|---|
| Offline & Private AI Text Detector | Score how AI-generated your writing reads, fully offline and private in your browser, with no signup and no paywall. | 2026-08-17 |
| Text Case Format Converter | camelCase, snake_case, SCREAMING_SNAKE, kebab-case, Title Case, PascalCase | 2026-05-07 |
| Flesch-Kincaid & SMOG Readability Scorer | Sentence-level highlights show exactly which lines drag your grade level down | 2026-04-27 |
| Reading Time Calculator (coming) | Reading time estimate at adjustable WPM targets | 2026-10* |
| Markdown Preview (coming) | Live-render Markdown with clean typeset output and copy-as-HTML export | 2026-10* |
| Tool | Description | Release date |
|---|---|---|
| WCAG Contrast Checker | AA and AAA contrast ratio testing with hex, RGB, and HSL input | 2026-07-10 |
| CSS Gradient Builder | Visual linear, radial, and conic gradient editor with live CSS output | 2026-06-07 |
| Color Format Converter | Convert between HEX, RGB, HSL, HSV, OKLCH, and CSS named colours | 2026-05-01 |
| Tool | Description | Release date |
|---|---|---|
| MIME Type Reference | Searchable MIME database with extension mapping and RFC sources | 2026-05-31 |
| IndexNow URL Submitter | Submit URLs to Bing, Yandex, Naver, and more via IndexNow | 2026-05-23 |
| HTTP Status Code Reference | Searchable reference for all HTTP 1xx to 5xx codes with usage notes | 2026-05-20 |
| P2P Network Tester | WebRTC peer-to-peer latency, jitter, and packet loss between two browsers | 2026-05-13 |
| IPv4 / IPv6 Subnet & CIDR Calculator | Network ranges, broadcast addresses, and host counts for IPv4 and IPv6 | 2026-05-06 |
| URL Parser & Inspector | Decompose any URL into protocol, host, path, query params, and fragment | 2026-05-03 |
| Tool | Description | Release date |
|---|---|---|
| Receipt Item Splitter | Assign receipt lines to people and split tax and tip on this device. Nothing uploaded. | 2026-09-17 |
| Phone-Scan Deskew to PDF | Straighten a trapezoid phone photo of a document into a clean, multi-page PDF on this device. Nothing uploaded. | 2026-09-14 |
| Local PDF Toolkit | Merge, split, reorder, rotate, and compress PDFs on this device. Nothing uploaded. | 2026-09-10 |
| Image Shrink-to-Limit | Reduce one image to an email, form, or app file-size cap on this device. Nothing uploaded. | 2026-09-10 |
| Passport & Visa Photo Cropper | Crop a passport or visa photo to official millimetre size and eye-line on this device. Nothing uploaded. | 2026-09-08 |
* Planned release
- Prepare a USCIS Filing Packet as Clean PDFs Without Uploading a Single Page - Assemble a USCIS filing packet with current form editions, clean scans, ordered merges, and portal-ready file sizes, all without uploading a page.
- After IndexNow: 6 Launch Channels Indie Founders Skip, and How to Hit Them in a Weekend - Six distribution channels solo founders skip, with weekend time budgets for each.
- Debugging API Responses Locally in the Browser: A JSON Formatter Workflow That Never Sends Your Payload - A three-minute local debugging routine for API responses: format, validate, locate the broken line, browse large payloads as a tree, and minify.
- Running an LLM in Your Browser: Verifying WebGPU, Model Hashes, and Local Inference Without a Server - Verify a local browser LLM before you trust it: check WebGPU support, hash the model file, and audit what your browser leaks while it runs.
- Post-Quantum TLS in 2026: What a Certificate Inspector Can and Cannot Tell You Yet - Half the web negotiates post-quantum handshakes while certificates stay classical. Run a five-minute local audit to see where your domains stand.
- Where Your Text Goes When You Check It for AI: Six Detectors Compared - Six AI detectors compared on signup, free caps, price, and where your text is actually processed, plus how to read a 99% accuracy claim.
Built with Astro and TypeScript. Installable as a PWA on desktop and mobile, or as a native app via the Microsoft Store.
