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JWT Decoder
Paste a JSON Web Token to decode its header and payload.
About JSON Web Tokens (JWT)
JSON Web Tokens (JWT) are an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. JWTs are commonly used for authentication and information exchange in web development.
JWT Structure
- Header: Contains token type and signing algorithm
- Payload: Contains claims (statements about an entity)
- Signature: Verifies the token hasn't been altered
- Parts are Base64Url encoded and separated by dots
- Format:
header.payload.signature
Common Uses
- Authentication systems
- Information exchange
- Authorization
- Secure API communication
- Single Sign-On (SSO) implementations
This tool only decodes JWT tokens and does not verify signatures. The signature verification requires the secret key used to sign the token. Never share sensitive JWT tokens publicly as they may contain private information.