Utilities that speed up everyday development.
A focused set of free developer tools — JSON formatter, regex tester, JWT decoder, hash generator, and more. Every tool runs locally in your browser so sensitive data (tokens, payloads, source code) never leaves your device.
Format, validate, and beautify JSON data with syntax highlighting.
Send HTTP requests, organize collections, manage environments, and test APIs — like Postman in your browser.
Encode text to Base64 or decode Base64 back to text.
Generate UUID v4 and v7 identifiers. Bulk generate and copy.
Paste JSON and get TypeScript types and interfaces instantly.
Test regular expressions with live matching, highlighting, and capture groups.
Convert between HEX, RGB, and HSL color formats with live preview.
Decode JSON Web Tokens to inspect header, payload, and expiry.
Encode or decode URL components and query strings.
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text.
Beautify SQL queries across dialects — PostgreSQL, MySQL, SQLite, and more. 100% in-browser.
Generate arrays of realistic fake data for testing — users, products, addresses, and custom schemas.
Beautify or minify HTML, CSS, and JavaScript/TypeScript — all in your browser.
Explain cron expressions in plain English and preview the next runs. All client-side.
Visually design CSS box-shadows with a live preview. Supports multi-layer stacks.
Design linear, radial, and conic CSS gradients with a live preview.
Visually design CSS border-radius shapes — from simple rounded corners to organic blobs.
Structural diff of two JSON objects — highlights added, removed, and changed keys.
Generate HMAC signatures (SHA-1/256/384/512) from a message and secret key. Uses WebCrypto.
Encrypt or decrypt text with a passphrase using AES-GCM. Runs entirely in your browser.
Generate BIP39 seed phrases (12/15/18/21/24 words) offline in your browser. Useful for cryptocurrency wallets.
Inspect Unicode code points, escapes, normalization forms, and byte breakdowns of any string.
Obfuscate JavaScript source code with low / medium / high presets — entirely in your browser.
Yes. Every tool on this page is free to use with no login, rate limits, or watermarks.
Yes. All developer tools here run entirely in your browser. Nothing is uploaded or logged.
After the first load the tools are cached and largely work offline. Some tools that pull external libraries on demand may need network on first use.