Free Online JWT Decoder and Parser
JSON Web Tokens (JWT) are an open standard used to share information securely between two parties. Our free online JWT Decoder allows you to paste your token and instantly view the decoded Header and Payload. The tool operates completely in your browser without transmitting your sensitive token data to any server, guaranteeing 100% privacy and security.
What is a JSON Web Token (JWT)?
A JSON Web Token consists of three parts separated by dots (.): the Header, the Payload, and the Signature.
- Header: Typically consists of two parts: the type of the token, which is JWT, and the signing algorithm being used, such as HMAC SHA256 or RSA.
- Payload: Contains the claims. Claims are statements about an entity (typically, the user) and additional data.
- Signature: Used to verify the message wasn't changed along the way, and, in the case of tokens signed with a private key, it can also verify that the sender of the JWT is who it says it is.
Why Use Our JWT Parser?
- Instant Decoding: Automatically decodes Base64Url encoded strings into human-readable JSON formats as soon as you paste the token.
- Client-Side Security: Decoding happens locally. Your tokens are not sent to any backend infrastructure.
- Easy Inspection: Perfect for debugging API authentication, checking token expiration (exp), or inspecting custom claims.
Disclaimer
This tool is intended for decoding and inspecting JWTs only. It does not validate the signature of the token. Never trust the contents of a JWT in your application without properly verifying the signature against your secret key or public key infrastructure on your backend.