A JSON Web Token (JWT) is a compact, URL-safe token format used for securely transmitting information between parties. It consists of three parts separated by dots: Header (algorithm and token type), Payload (claims/data), and Signature (verification hash). JWTs are commonly used for authentication, authorization, and information exchange in web applications and APIs.
Paste any JWT token into the input field above. The decoder will automatically parse and display the header, payload with human-readable claim labels, and signature. It also checks if the token has expired. All decoding happens entirely in your browser — your token is never sent to any server.