JWT Decoder
Decode and inspect JSON Web Tokens to view header, payload, and check expiration.
Enter JWT Token
Header
Decoded header will appear here
Payload
Decoded payload will appear here
🔒 Privacy First: All decoding happens locally in your browser. Your tokens never leave your device.
What is a JWT?
JSON Web Token (JWT) is an open standard (RFC 7519) for securely transmitting information between parties as a JSON object. JWTs are commonly used for authentication and authorization in web applications. They consist of three parts: header, payload, and signature.
JWT Structure
- Header: Contains token type and signing algorithm (e.g., HS256, RS256)
- Payload: Contains claims - user data and metadata (iss, sub, exp, iat, etc.)
- Signature: Verifies the token hasn't been tampered with
Common JWT Claims
- iss: Issuer - who created the token
- sub: Subject - who the token is about
- exp: Expiration time (Unix timestamp)
- iat: Issued at time
- aud: Audience - intended recipients
Related Utilities
Explore our other free developer tools: Base64 Encoder, JSON Formatter, Hash Generator, and Timestamp Converter.