The JWT Decoder is a free online tool that lets you decode a JWT header & payload (no verification) — so you can format, convert and debug without installing anything. Everything runs locally in your browser, so it is fast, completely private, and works even when you are offline.
Whether you are a developer, tester or student, the JWT Decoder gives you instant results with no installation, no account and no limits.
Yes. The JWT Decoder is completely free with no sign-up, no usage limits and no watermarks. Use it as many times as you like.
Absolutely. The JWT Decoder processes everything inside your browser — your input is never uploaded to any server, so your data stays 100% private.
Yes. All processing happens in your browser using JavaScript, so once the page has loaded you can keep using it with no internet connection — and none of your code or data is ever sent to a server.
No installation needed. The JWT Decoder works in any modern browser on desktop, tablet and mobile.
No — it only decodes the header and payload so you can inspect the claims. Signature verification needs the secret/public key and should be done server-side.