Developer Tools

Developer tools

A privacy-first toolbox for developers — format JSON, diff code, hash files, encode data, and check colors. Everything runs locally in your browser.

JSON Formatter

Format, beautify, and validate JSON data.

Code Diff Tool

Compare code changes with monospace formatting.

Text Diff Checker

Compare two texts and see every difference.

Base64 Encoder / Decoder

Encode or decode strings to and from Base64.

URL Encoder / Decoder

Percent-encode text or decode safe URLs.

Text Hash Generator

Hash text with SHA-256, SHA-1, SHA-384, or SHA-512.

File Hash Generator

Generate SHA-256, SHA-1, and MD5 checksums for files.

WCAG Contrast Checker

Test color contrast for AA/AAA accessibility.

Color Picker

Pick colors and get HEX, RGB, and HSL values.

Coder Typing Test

Test your typing speed on real code snippets.

Keyboard Tester

Check that every key on your keyboard registers.

JSON to CSV

Convert a JSON array to a CSV file.

Frequently asked questions

Are these developer tools free?: Yes. Every tool is free, requires no account, and runs entirely in your browser. Your data never leaves your device.
Do these tools work offline?: Most are pure client-side JavaScript, so once the page loads they keep working without a network connection.
Is my code or data uploaded to a server?: No. Formatting, hashing, diffing, and encoding all happen locally in the browser. Nothing is transmitted or stored.