Development Tools

A community-driven, open source collection of quick-start guides ("The TL;DR of everything"). Provides 124+ free guides for tools and technologies like Docker, without requiring any account or login.

A browser-based debugger for JSON Web Tokens. Paste any JWT to instantly decode its header, payload, and signature. Verify token signatures with your secret or public key. Supports HS256, RS256, ES256, and other common algorithms — all processing happens in your browser with no account required.

Online regex tester and debugger for PHP, PCRE, Python, Golang, and JavaScript. Build, test, and debug regex patterns with real-time explanation and match highlighting.

Up-to-date browser support tables for web technologies including HTML5, CSS3, SVG, and JavaScript APIs. Essential reference for web developers.

The Cyber Swiss Army Knife — encode, decode, encrypt, compress, and analyze data with a drag-and-drop recipe builder.

Visual cron expression editor with human-readable explanations. Quickly build and validate cron schedules.

Find the cost of adding an npm package to your bundle. View size, download time, and composition of any package.

Parse and explain shell commands. Paste any command line to get a detailed breakdown of each argument and flag.

Instantly test and debug webhooks and HTTP requests. Get a unique URL to inspect incoming requests in real time.

Collection of 70+ developer utilities: hash generators, encoders, converters, formatters, and more — all in one place.

Interactive compiler explorer that shows assembly output for 60+ languages. Compare compilers and optimization levels side by side.

Official Go online compiler and execution environment. Write, compile, and run Go code directly in the browser.

Create flowcharts, sequence diagrams, Gantt charts, and more using simple text syntax. Live preview with export to SVG/PNG.

Check HTML and CSS support across email clients. Like Can I Use, but for email — know what works in Gmail, Outlook, Apple Mail, and more.

Simple HTTP request and response service for testing. Inspect headers, cookies, auth, redirects, and response formats.

Preview and generate social media meta tags. See how your page looks on Google, Facebook, Twitter, LinkedIn, and more.

Combines multiple API documentations in a fast, organized, and searchable interface. Covers JavaScript, HTML, CSS, Node.js, Ruby, Python, and hundreds more.

Create and share beautiful images of your source code. Choose from dozens of syntax themes, languages, and export to PNG or SVG.

Online JSON formatter, validator, and viewer. Paste or upload JSON data to format, validate, minify, and convert between JSON and other formats.

Write, compile, and run TypeScript code in the browser. Official Microsoft tool with full type checking and IntelliSense.

Create beautiful code screenshots with customizable themes, backgrounds, and padding. By Raycast.

Official Rust online compiler and execution environment. Write, compile, and run Rust code directly in the browser.

Open-source API development ecosystem. Test REST, GraphQL, WebSocket, and more — a lightweight Postman alternative.

Visualize and explore Abstract Syntax Trees for many languages and parsers. Essential tool for compiler and tooling development.

Compare npm package download trends over time. See package sizes, GitHub stars, and make informed dependency decisions.

Generate quality badges for your README and documentation. Hundreds of integrations for build status, coverage, version, and more.

Preview Prettier code formatting results online. Experiment with options and see formatted output for JavaScript, TypeScript, CSS, and more.

Web accessibility evaluation tool by WebAIM. Enter any URL to get a detailed accessibility report with WCAG compliance checks.

A simple yet powerful Chrome extension that helps you extract and export cookies from any website with just one click.

This is a tool website forked from it-tools, containing 100+ tools.