Developer Tools Collection

15+ Free online tools for developers

All tools run locally in your browser. No data sent to server. Fast, secure, and privacy-focused.

QR Generator

Generate QR codes from text, URLs, and more

Runs in browser→

QR Scanner

Scan and decode QR codes from images

Runs in browser→

URL Parser

Parse and analyze URL components

Runs in browser→

JSON Formatter

Format, validate and beautify JSON

Runs in browser→

Markdown Renderer

Preview and render Markdown text

Runs in browser→

JWT Decoder

Decode and verify JWT tokens

Runs in browser→

Base64 Converter

Encode and decode Base64 strings

Runs in browser→

Hex Converter

Convert between hex and text

Runs in browser→

Escape Decoder

Decode HTML and URL escape sequences

Runs in browser→

Hash Calculator

Generate MD5, SHA1, SHA256 hashes

Runs in browser→

UUID Generator

Generate UUID v1, v4 identifiers

Runs in browser→

Random Number Generator

Generate random numbers in range

Runs in browser→

Random String Generator

Generate random strings with custom patterns

Runs in browser→

Block Puzzle Solver

Solve block sliding puzzles

Runs in browser→

ZIP Tool

Compress and extract ZIP files

Runs in browser→

About Dev66

Dev66 provides a comprehensive collection of developer tools that work entirely in your browser.

All tools are open source and available for free. No registration required, no data collection.

✅ All tools work offline

✅ No data sent to server

✅ Fast and lightweight

✅ Mobile friendly

✅ Open source

Need help or want to suggest new tools?

Create an Issue on GitHub