Paste a JWT (three base64url segments separated by dots) to see its decoded header and payload as JSON.
All tools/Encoding
JWT Decoder
Decode a JSON Web Token's header and payload. Runs entirely in your browser — the signature is never verified or checked against a server.
Header
Payload
How this works & FAQ
Does this verify the signature?
No. Decoding a JWT only reveals its header and payload, which anyone can read — it does not prove the token is authentic. Verifying the signature requires the issuer's secret or public key, which this tool never asks for.
Is my token uploaded anywhere?
No. Decoding happens entirely in your browser using JavaScript's built-in Base64 decoding.