JWT Decoder
Decode and inspect JSON Web Tokens to view the header, payload, and signature. Processing runs in your browser.
Token Breakdown
HDR Header
PLD Payload (Claims)
SIG Signature
About JWT Tokens
What is a JWT? JSON Web Token (JWT) is a compact, URL-safe format for claims passed between parties. JWTs are commonly used for authentication and authorization.
JWT structure:
- Header - token type and signing algorithm (e.g. HS256, RS256)
- Payload - claims about the subject and metadata
- Signature - verifies the token was not tampered with
Security note: JWT payloads are Base64URL-encoded, not encrypted. Never store passwords or secrets in JWT tokens.