Developer Tools
Free, fast, and runs in your browser. No data sent to servers.
All Tools
JSON Formatter
Format, validate and minify JSON
Base64 Encode/Decode
Encode or decode Base64 strings
URL Encode/Decode
Encode or decode URL components
Regex Tester
Test and debug regular expressions
Cron Expression
Generate and explain cron expressions
JWT Decoder
Decode and inspect JWT tokens
Hash Generator
Generate SHA-1, SHA-256, SHA-512 hashes
Color Converter
Convert between HEX, RGB, HSL
Diff Checker
Compare two blocks of text
Markdown Preview
Preview Markdown in real time
Text Case Converter
Convert to uppercase, camelCase, snake_case and more
Word Counter
Count words, characters, sentences and paragraphs
Password Generator
Generate strong, random passwords
Number Base Converter
Convert between binary, hex, octal, decimal
Timestamp Converter
Convert Unix timestamps to dates and back
Free Online Developer Tools
DevToolbox is a collection of free, fast, browser-based tools for developers. Every tool runs entirely in your browser — no data is ever sent to a server.
Encoding & Decoding
Tools like Base64 Encoder and URL Encoder help you quickly convert data for use in APIs, emails, and web requests.
Data Formatting & Validation
The JSON Formatter validates and pretty-prints JSON instantly. The Diff Checker highlights line-by-line differences between two texts.
Security & Cryptography
Use the JWT Decoder to inspect token payloads, or the Hash Generator to compute SHA-256 and other hashes.
Developer Utilities
The Regex Tester highlights matches in real time. The Cron Generator explains cron schedules in plain English.