Dev Tool box - Developer Tools

Ten developer utilities in one app. Format JSON, encode a URL, decode a JWT — without opening your laptop.

- JSON Formatter — pretty-print and validate JSON, with a tree view and search
- URL Encode/Decode — RFC 3986 compliant
- Base64 Encode/Decode — URL-safe variant and auto-padding included
- JWT Decoder — split a token into header, payload and signature (decode only, no signature check)
- Text Case Converter — 9 cases: camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE_CASE, dot.case, Title Case, UPPERCASE, lowercase
- Hash Generator — MD5, SHA-1, SHA-256 and SHA-512 at once
- Unix Timestamp Converter — seconds and milliseconds, ISO 8601, UTC and local time
- Number Base Converter — decimal, binary, octal and hexadecimal, with 0x / 0b / 0o detection
- String Escape/Unescape — handle escape sequences in strings
- Color Converter — HEX to RGB and HSL with a live preview and ready-to-paste code snippets

- Auto-save: your input comes back the next time you open a tool
- One-tap copy to clipboard
- Dark mode
- Every conversion runs on the device — your input is never uploaded

The app interface is in English only.

Contact: [email protected]