Developer Tools

16 free developer tools: JSON formatter, regex tester, base64 encoder, hash generator, JWT decoder, diff checker, and more. No signup required.

16 free tools

JSON Formatter & Validator

Format, minify, and validate JSON with syntax highlighting. See structure stats and errors with line numbers.

Regex Tester

Test regular expressions with live match highlighting, capture groups, and match details.

Base64 Encode / Decode

Encode text to Base64 or decode Base64 to text. Handles Unicode characters correctly.

URL Encode / Decode

Encode or decode URLs and query parameters. Supports encodeURI and encodeURIComponent modes.

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text using Web Crypto API.

JWT Decoder

Decode JSON Web Tokens to inspect header, payload, and expiration. No verification, just decoding.

Diff Checker

Compare two texts side by side. See added, removed, and unchanged lines with color highlighting.

Cron Expression Generator

Build and decode cron expressions with a visual editor. See human-readable descriptions and next run times.

CSS Minifier & Beautifier

Minify CSS to reduce file size or beautify compressed CSS for readability. Shows size savings.

HTML Entity Encoder / Decoder

Encode special characters to HTML entities or decode entities back to text. Supports named and numeric entities.

Subnet Calculator

Calculate network address, broadcast address, subnet mask, usable hosts, and CIDR from any IP address.

Binary Translator

Translate between text and binary, hex, decimal, or octal. Convert in both directions instantly.

Download Time Calculator

Estimate how long a file will take to download at your connection speed. Supports KB, MB, GB, TB and all speed units.

Hex to RGB Converter

Convert between hex, RGB, and HSL color formats. Check WCAG contrast ratios and copy CSS color values.

ASCII Table

Interactive ASCII reference table with search, paste-to-inspect, reverse lookup, range filters, and one-click copy.

Unicode Lookup

Search and browse Unicode characters, emoji, and symbols. Click to copy in any format with block and category filters.