Developer Toolkit: JSON, JWT, Regex & More

JSON formatter, JWT decoder & signer, regex tester, Base64, hashes, QR codes and more. Free, 100% offline, no tracking.

Your browser is where you do your work, so the tools you use every day should live there too. Inside Developer Toolkit you will find a JSON formatter and validator, a JWT decoder and signer, Base64 and URL encoders, a regex tester, hash, UUID and password generators, a QR code generator, a text diff checker, a cron builder, SQL and Markdown tools, timestamp and color converters, an image compressor, and quick references for the small things you should never have to Google. And that list is not final: the toolkit keeps growing, with new tools added regularly. It is built to feel like a real app, not a cramped little popup. Open it in its own resizable window or dock it in Chrome's Side Panel. Choose a light, dark or system theme, pin the tools you use most as favorites, and reach anything instantly with search, a command palette, the keyboard, or a right click on selected text. Every tool is designed the same calm way, so once you know one, you know them all. It even opens where you left it, the way a tool you rely on should. Most importantly, it respects your data. Every tool runs entirely in your browser: no accounts, no analytics, no network requests, nothing uploaded anywhere. Paste a token, a key or a private snippet, and it never leaves your machine.