JWT Debugger
Decode and debug your JSON Web Tokens instantly.
Client-side only. Your tokens never leave your browser.
How to Debug JWTs?
JSON Web Tokens (JWT) are widely used for authentication. This debugger allows you to:
- Inspect Claims: See exactly what data is inside the token (User ID, Expiry, Roles).
- Verify Structure: Check if the token has the correct Header, Payload, and Signature structure.
- Debug Expiration: Check the `exp` claim to see if your token is expired.
Note: We do not verify the signature because that requires your secret key, which should never be shared.
Understanding JSON Web Tokens (JWT)
JWT (pronounced "jot") is the open standard (RFC 7519) for securely transmitting information between parties as a JSON object. It is the backbone of modern Stateless Authentication.