Developer Tools, In Your Browser
Free, open-source utilities for developers. No signup, no server processing — your data never leaves your browser.
JSON Formatter
Format, validate, and beautify JSON with syntax highlighting and tree view.
Base64 Encode/Decode
Encode and decode Base64 strings and files with drag-and-drop support.
JWT Decoder
Decode JSON Web Tokens to inspect header, payload, and verify signatures.
Cron Expression Builder
Build and validate cron expressions with a visual editor and next run times.
Regex Tester
Test regular expressions with real-time match highlighting and capture groups.
UUID Generator
Generate, validate, and inspect UUIDs in v4 and v7 formats.
Timestamp Converter
Convert between Unix timestamps and human-readable dates with timezone support.
URL Encode/Decode
Encode and decode URLs, parse query parameters, and build query strings.
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes for text and files.
Color Converter
Convert colors between HEX, RGB, HSL formats with contrast checker and palette generator.
Diff Viewer
Compare two texts side by side with line-by-line and character-level diff highlighting.
Chmod Calculator
Convert between symbolic (rwx) and numeric (octal) Unix file permissions interactively.
HTML Entity Encode/Decode
Encode and decode HTML entities, named characters, and Unicode escape sequences.
JSON ↔ YAML Converter
Convert between JSON and YAML formats instantly with syntax validation.
HTTP Status Codes
Browse, search, and learn about all HTTP status codes with detailed explanations.