JWT Decoder
Decode and inspect JSON Web Tokens without verification.
JWT Token
What is a JWT Token Decoder?
A JWT (JSON Web Token) is a compact, URL-safe token format used for authentication and information exchange. A JWT consists of three Base64URL-encoded parts separated by dots: a Header, a Payload, and a Signature. This tool decodes and displays all three parts.
Common Use Cases
Inspecting JWT tokens during API debugging
Checking token expiry time (exp claim)
Verifying token contents without a backend
Understanding what claims an auth server is sending
Debugging OAuth 2.0 and OpenID Connect flows
Tips & Best Practices
The exp claim is a Unix timestamp — use our Timestamp Converter to convert it to a readable date
Never share your JWT with anyone — it contains your authentication credentials
Check the iat (issued at) and nbf (not before) claims for time-based issues
Frequently Asked Questions
What is a JWT token?▼
JWT (JSON Web Token) is an open standard (RFC 7519) for securely transmitting information as a JSON object. JWTs are commonly used for authentication — after login, the server returns a JWT which the client sends with every subsequent request.
Is JWT decoding the same as verification?▼
No. Decoding reads the contents of the token. Verification checks the signature using a secret key to confirm the token is authentic and has not been tampered with. This tool only decodes — it does not verify signatures.
What is the exp claim?▼
The exp (expiration time) claim is a Unix timestamp indicating when the token expires. After this time the token is no longer valid.
Is my JWT data safe here?▼
Yes — all decoding runs in your browser. Your token is never sent to any server. However, be cautious when pasting tokens from production systems.