A JWT (JSON Web Token) Decoder is a tool that translates the encoded Base64 strings of a web token into readable JSON format. JWTs are commonly used for authentication and information exchange in modern web applications.
This tool helps developers debug authentication issues by allowing them to verify the contents of the payload (such as user ID, roles, and expiration time) and the header (encryption algorithm) without sending the token to a server.
This JWT Decoder runs entirely in your browser (Client-Side). Your tokens are never sent to our servers or stored anywhere. However, as a best practice, avoid pasting highly sensitive production tokens with live credentials into any public web tool.
Contains metadata about the token, such as the type ("JWT") and the signing algorithm being used (e.g., HMAC SHA256 or RSA).
Contains the "claims". Claims are statements about an entity (typically, the user) and additional data like expiration time (exp).
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.