JWT Decoder

Decode JWT header and payload quickly in the browser.

JWT Decoder

Decode JWT header and payload (no signature verification).

Privacy note: JWT decoding happens in-browser only. Nothing is uploaded.

JWT Structure at a Glance

A JSON Web Token has three parts:

header.payload.signature

The header and payload are Base64URL-encoded JSON. The signature is used to verify integrity.

What This Tool Does

This JWT decoder helps you inspect header and payload claims quickly during debugging. It is useful for checking fields like sub, aud, iss, and exp.

Security Note

Decoding a JWT is not the same as verifying it. Always validate the signature and claims on the backend before trusting a token.