Free Developer Tools

JSON formatting, URL encoding, JWT decoding, regex testing, and more. No signup required. Use in your browser or integrate via API.

JSON Formatter & Validator

Format, validate, and analyze JSON with smart auto-fix for common issues. Sort keys, adjust indentation, and get detailed stats.

POST /api/v1/tools/json-format

URL Encoder / Decoder

Encode or decode URLs and query parameters with full component breakdown. Supports encodeURIComponent and decodeURIComponent.

POST /api/v1/tools/url-encode

Base64 Encoder / Decoder

Encode or decode Base64 in standard or URL-safe variants. Perfect for data URIs, JWTs, and binary-safe text encoding.

POST /api/v1/tools/base64

JWT Decoder

Decode and inspect JSON Web Tokens instantly. View header, payload, signature, expiration status, and registered claims.

POST /api/v1/tools/jwt-decode

Regex Tester

Test regular expressions with real-time match highlighting, group capture display, and flag configuration.

POST /api/v1/tools/regex-test

UUID / GUID Generator

Generate UUIDs v4 and v7. Bulk generation up to 100, uppercase/lowercase, with or without dashes.

POST /api/v1/tools/uuid-generate

HTTP Status Codes Reference

Complete reference for all HTTP status codes with descriptions, common causes, and troubleshooting tips.

Cron Expression Generator

Generate and explain cron expressions with human-readable descriptions and next run time previews.

POST /api/v1/tools/cron-explain

User Agent Parser

Parse any user agent string to extract browser, OS, device type, and rendering engine. Detects bots and mobile devices.

POST /api/v1/tools/parse-user-agent

robots.txt Generator & Tester

Generate robots.txt files with rule builder and presets. Test if URLs are allowed or blocked by any robots.txt.

POST /api/v1/tools/robots-txt-generate

Color Picker & Converter

Convert colors between HEX, RGB, HSL formats. Generate palettes and check WCAG contrast ratios for accessibility.

POST /api/v1/tools/color-convert

Free API Access

All tools are available via free API endpoints — no authentication required. Each endpoint accepts a POST request with a JSON body and returns processed results. Perfect for AI agents, scripts, and automation. Check each tool page for usage examples in curl, Python, and JavaScript.