The best free online developer tools
A toolbox of the small utilities developers reach for daily. They are instant, free, and run client-side, so you can safely paste tokens and payloads without them leaving your machine.
Tool list
JSON Formatter
Beautify, validate and minify JSON.
JWT Decoder
Decode and inspect JWT tokens locally.
Base64 Encode/Decode
Encode and decode Base64.
Hash Generator
Generate MD5, SHA-1, SHA-256 hashes.
Regex Tester
Test regular expressions with live matches.
UUID Generator
Generate UUIDs in bulk.
SQL Formatter
Format and tidy SQL queries.
JSON to TypeScript
Turn JSON into TypeScript interfaces.
FAQ
Is it safe to paste a JWT or payload here?
Yes — these tools run entirely in your browser, so tokens and data are never transmitted to a server.
Do I need to install anything?
No. Everything runs in the browser with no signup or install.