I built 12 free developer tools that run entirely in your browser

For the past few weeks I've been building DevCrate — a suite of developer tools that run 100% in your browser. No login, no ads, no data leaving your machine. Why I built it I kept switching between tabs every time I needed to format JSON, decode a JWT, or test a regex. Most tools either had ads, required an account, or I wasn't sure what they were doing with my data. So I built my own. What's live REST Client — send HTTP requests and inspect responses JSON Transformer — format, minify, convert to YAML/CSV JWT Debugger — decode and inspect tokens Regex Studio — live match highlighting with flag toggles SQL Formatter — supports PostgreSQL, MySQL, SQLite, BigQuery WebSocket Tester — connect, send, inspect frames in real time Base64 / Hash — encode, decode, MD5, SHA-256 Cron Builder — visual editor with human-readable output URL Inspector — parse, encode, decode URLs Diff Tool — compare text and JSON line by line Timestamp Converter — Unix to date and back, with timezones HTML Formatter —