JWT Decoder & Debugger
Decode and inspect JSON Web Tokens (JWT) to view header, payload, and signature information. Verify token signatures and check expiration status. All processing happens in your browser for maximum security.
JWT Token
Decoded JWT
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Paste a JWT token in the input field and click "Decode Token" to see its contents. All processing happens in your browser - your tokens are never sent to any server.
About JWT Tokens
JSON Web Tokens (JWT) are an open standard (RFC 7519) that define a compact and self-contained way for securely transmitting information between parties as a JSON object. JWTs are commonly used for authentication and information exchange in web applications.
JWT Structure
- Header - Contains the token type and the signing algorithm being used
- Payload - Contains the claims or the JSON object with the data being transmitted
- Signature - Used to verify that the sender of the JWT is who it says it is and to ensure the message wasn't changed along the way
Common Claims
- iss (Issuer) - Who issued the token
- sub (Subject) - Who the token refers to
- aud (Audience) - Who the token is intended for
- exp (Expiration Time) - When the token expires
- nbf (Not Before) - When the token starts being valid
- iat (Issued At) - When the token was issued
- jti (JWT ID) - Unique identifier for the token