Free Developer Tools Online

A curated collection of developer utilities that run entirely in your browser. No data leaves your computer—fast, private, and free.

Data Formatting

JSON Formatter

Beautify JSON with proper indentation

JSON Validator

Validate JSON syntax and find errors

HTML Formatter

Format and beautify HTML code

CSS Formatter

Format CSS with proper indentation

Encoding & Hashing

Base64 Encode/Decode

Convert to and from Base64

URL Encoder/Decoder

Encode special characters for URLs

Hash Generator

MD5, SHA-1, SHA-256, SHA-512

JWT Decoder

Decode and inspect JWT tokens

IDs & Security

UUID Generator

Generate random UUID v4 identifiers

Password Generator

Create secure random passwords

Password Strength Checker

Test password security

Pattern Matching

Regex Tester

Test regular expressions with matches

Simple Regex Tester

Quick regex pattern testing

Email Extractor

Extract emails from text

Time & Scheduling

Unix Timestamp Converter

Convert timestamps to dates

Cron Validator

Test cron expression schedules

Time Zone Converter

Convert between time zones

Number Systems

Base Converter

Convert between bases 2-36

Binary to Decimal

Convert binary numbers

Decimal to Hex

Convert to hexadecimal

ASCII Table

Character codes reference

Unix/Linux

Chmod Calculator

Calculate file permissions

Learn More

Read our developer guides to get the most out of these tools.

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