PyChallenge
Stop reading tutorials. PyChallenge gives you real Python exercises that run right in your browser. No install, no signup. Instant feedback, hints, and XP.
Other Developer tools tools
Launch OrbitInstead of displaying launches as another endless list or feed, LaunchOrbit places products on a shared, interactive canvas. Founders can add their product, upload their website logo or create a custom art tile, and link directly to their site. Visitors can: Explore the launch board Discover new products and SaaS tools Search by category Upvote launches Open dedicated product pages See which products are gaining community attention The idea is to make product discovery more visual, memorable, and persistent—so a launch doesn’t disappear after a single post or launch day.
CTlogs.ioWhat it does Search over the public Certificate Transparency logs: 45B+ certificate records across 638M domains. Queries Subdomains of a registered domain, as seen in issued certificates Certificates issued for a hostname: issuer, SANs, validity window, date first logged Lookup by SHA-256 fingerprint Keyword search over the last few weeks of issuance, where new phishing and look-alike hostnames first appear Access 3 searches a day as a guest, 5 a day per query type with a free account, no card Paid plans from $29.99 a month add CSV export, a REST API and an MCP connector for AI assistants Six free tools: subdomain finder, certificate history, expiry checker, CA lookup, fingerprint lookup, brand impersonation scanner
Number Generator 1 to 100Free number generator 1 to 100. Pick one random number or a full list, turn on no repeats for fair draws, and copy the result. Fast, private, no sign up.
YYLOYYLO Ledger (GitHub) is an open-source, Git-native task manager and Record store for developers, automation tools, and AI coding-agent workflows. It provides a shell-friendly CLI for creating tasks, tracking dependencies, recording progress, preserving history, and querying project work without making a hosted database the source of truth. Ledger keeps canonical current state in reviewable Markdown files inside the repository and records opt-in history in segmented, hash-chained ledgers. A disposable SQLite cache accelerates broader queries but can be rebuilt from the canonical files. This design makes project tasks easier to review, version, audit, and coordinate alongside source code. Beyond task tracking, YYLO Ledger supports typed Records for wikis, workflows, and artifacts. It offers bounded structured output for scripts, dependency-aware task ordering, integrity checks, immutable cold archives, preservation-first migration tools, and a read-only local Record host. YYLO Ledger is part of the wider YYLO developer-tool ecosystem. Use it independently as a Git-based task management CLI, connect it with YYLO CLI (GitHub) for AI coding-agent orchestration and guarded software delivery, or pair it with YYLO Benchmark (GitHub) for evaluation and evidence workflows. Product page: YYLO Ledger on yylo.dev Source code: YYLO Ledger on GitHub Python package: yylo-ledger on PyPI AI agent orchestration: YYLO CLI on yylo.dev · GitHub · npm Evaluation tooling: YYLO Benchmark on yylo.dev · GitHub · npm
dochostTurn HTML to URL and Markdown to HTML in seconds. A free HTML host and Markdown host with a live Markdown preview — paste, get a link, no signup.
Online Tone GeneratorGenerate tones at any frequency and download WAV files. A free online tone generator with sine, square, triangle, and sawtooth waveforms. No sign-up.
