JWT Decoder
The JWT Decoder is a secure tool that allows you to decode and inspect JSON Web Tokens (JWT) directly in your browser. It breaks down the token into its three components: Header, Payload, and Signature. For your security, all decoding is performed locally on your device—your tokens are never sent to our servers.
What is a JSON Web Token (JWT)?
JWT is an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. This information can be verified and trusted because it is digitally signed.
- Header: Typically consists of two parts: the type of the token (JWT) and the signing algorithm being used (e.g., HS256 or RS256).
- Payload: Contains the claims. Claims are statements about an entity (typically, the user) and additional data.
- Signature: Used to verify that the sender of the JWT is who it says it is and to ensure that the message wasn't changed along the way.
Security & Privacy
Decoding a JWT does not require a secret key; the information is merely Base64Url encoded. However, you should never share tokens containing sensitive information with untrusted parties. Our tool ensures your data stays private by processing everything client-side.