Free Online Developer Tools

Fast, free, and private. All tools run in your browser — no data leaves your device. No signup required.

All Tools

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JSON Formatter

Developer

Format, validate, and minify JSON data instantly

B64

Base64 Encoder/Decoder

Developer

Encode and decode Base64 strings and files

JWT

JWT Decoder

Developer

Decode and inspect JSON Web Tokens

#

Hash Generator

Developer

Generate MD5, SHA-1, SHA-256, SHA-512 hashes

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Regex Tester

Developer

Test regular expressions with live highlighting

%

URL Encoder/Decoder

Developer

Encode and decode URLs and query strings

Aa

Word & Character Counter

Text

Count words, characters, sentences, and reading time

🎨

Color Converter

Design

Convert between HEX, RGB, HSL color formats

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Lorem Ipsum Generator

Text

Generate placeholder text for your designs

MD

Markdown Preview

Text

Write and preview Markdown in real time

Free Developer API

API

DevToolBox API

18+ endpoints, no API key needed

Free REST API: URL shortener, hash generator, UUID, placeholder images, random data, and more. 100k requests/day.

Why DevToolBox?

100% Client-Side

All processing happens in your browser. Your data never leaves your device.

No Signup

Just open and use. No accounts, no tracking, no nonsense.

Always Free

Core tools are free forever. No paywalls on essential features.