JSON Web Token (JWT) Decoder
Decode JWT headers, payload claims, and token expiration status 100% locally in your browser.
JSON Web Token (JWT) Structure & Claims Reference
JSON Web Tokens are an open, industry-standard RFC 7519 method for representing claims securely between two parties.
1. Three Token Components
JWTs consist of three dot-separated Base64URL parts: Header.Payload.Signature.
2. Expiration Verification
Inspect registered claims like exp (expiration time) and iat (issued at).
3. Privacy Protection
Decoding runs 100% in client JavaScript. Sensitive auth tokens are never logged or stored on any server.