Free Developer Tools Tools

Regex, HTTP and API debugging, config validators and ID generators for everyday development.

• Regex Lab: Test and explain regular expressions, and extract matches and structured data from text.
  • Regex Playground & Explainer
  • Regex Match & Data Extractor
• HTTP & API Toolkit: Status codes, security header analysis, webhook testing, mock responses, GraphQL and OpenAPI helpers, user agents and subnets.
  • HTTP Status Code Reference
  • HTTP Security Header Analyzer
  • User-Agent Parser
  • Webhook Tester
  • HTTP Mock Response Generator
  • Fake API Response Generator
  • GraphQL Query Builder
  • OpenAPI & Swagger Validator
  • Subnet & CIDR Calculator
• Project & Config Toolkit: Validate tsconfig, package.json, Docker files and env files, and generate ESLint configs, .gitignore files and changelogs.
  • TSConfig Validator & Explainer
  • Package.json Validator & Auditor
  • Docker Compose Linter
  • Dockerfile Best Practices Linter
  • ESLint Flat Config Builder
  • .gitignore Generator
  • Changelog Generator
  • ENV File Manager
  • SemVer Calculator
  • NPM Package Size Estimator
• UUID & ID Generators: Generate random UUID v4 and NanoID values in bulk, or deterministic UUID v3 and v5 from a namespace and name.
  • UUID & NanoID Generator
  • UUID v3 & v5 Namespace Generator
• CSS Workshop: Specificity, grid and flexbox builders, 3D transforms, Sass and LESS compiling, PostCSS and CSS variables.
  • CSS Specificity Calculator
  • CSS Grid Builder
  • CSS Flexbox Playground
  • CSS Variable Inspector
  • Sass / LESS → CSS Compiler
  • CSS 3D Transform Builder
  • PostCSS Playground
  • CSS Border-Radius Builder
  • CSS Filter Playground
• Developer Playground: TypeScript, JSX, SQL, YAML and TOML converters plus git, npm, semver and env helpers.
  • TypeScript Playground (Mini)
  • HTML to JSX Converter
  • SQL Query Explainer
  • YAML ↔ TOML Converter
  • Git Command Builder
  • npm Package Search
  • Environment Variable Formatter
  • Timestamp Format Reference
  • JSON Schema Generator
• Auth & Identity Toolkit: OAuth 2.0 flows, SAML assertions, SSL/TLS certificates, SSH fingerprints and an HTTP request builder.
  • OAuth 2.0 Flow Debugger
  • SAML Assertion Decoder
  • SSH Key Fingerprint Calculator
  • HTTP Request Builder & Sender
• Advanced Dev Utilities: Protobuf and WebAssembly inspectors, API calculators, ESLint rules, web vitals, SVG to React, email HTML and accessibility audits.
  • Protocol Buffer Inspector
  • WebAssembly Inspector
  • API Rate Limit Calculator
  • API Payload Size Calculator
  • ESLint Rule Explainer
  • Docker Image Tag Browser
  • Web Vitals Budget Checker
  • Color Token Generator
  • SVG to React Component
  • HTML Email Tester
  • HTML Email Signature Builder
  • APCA Contrast Checker
  • Accessibility Audit Suite

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