JWT Decoder
Decode JSON Web Tokens (JWT) instantly in your browser. Verify the header and payload claims without sending your token to any server.
Decoded header will appear here...
Decoded payload will appear here...
Signature will appear here...
What is a JWT?
A JWT (JSON Web Token) is an open standard (RFC 7519) for securely transmitting information between parties as a JSON object. A JWT has three parts: the Header (signing algorithm), the Payload (claims/data), and the Signature (used to verify the token), joined by dots.
How to use this JWT decoder
- Paste your JWT into the box on the left
- The Header, Payload, and Signature are decoded automatically and shown on the right
- Everything runs in your browser — your token is never sent to a server
Frequently asked questions
Does this tool verify the JWT signature?
No, this is a decode-only tool for inspecting the header and payload. Verifying the signature requires the secret or public key and should be done on the backend.
Is my token sent to a server?
No. Decoding happens entirely client-side in JavaScript, so sensitive data in your token stays in your browser.