JWT Debugger
Decode and inspect JSON Web Tokens (JWT) payload, header, and signature parts.
What is a JSON Web Token (JWT)?
JSON Web Token (JWT) is an open standard that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. They are widely utilized in modern web apps for user authentication and information exchange.
Anatomy of a JWT Structure
- Header: Consists of two parts: the token type (JWT) and the signing algorithm being used, such as HMAC SHA256 or RSA.
- Payload: Contains the claims or user data payload, including identity information, permissions, and expiration metadata.
- Signature: Used to verify that the sender of the JWT is who they say they are and to ensure the message wasn't tampered with along the way.
Client-Side Security and Privacy
This debugging utility runs entirely inside your browser using client-side scripts. Your sensitive tokens and custom claims are never sent, logged, or saved on any external servers.