JWT Decoder

Instantly decode a JWT to inspect its claims and spot misconfigured subject, audience, or issuer values causing 401 errors. No libraries needed. Just paste the token.

Security engineers can audit JWT payloads for overly permissive scopes, missing expiry (exp) claims, or weak algorithm choices (e.g. none or HS256 with a short secret).

QA teams can verify that the correct roles, scopes, and user attributes are embedded in tokens returned by the auth service after login or token refresh flows.

See the three-part header.payload.signature structure decoded side by side. Great for developers learning about JSON Web Tokens, Base64url encoding, and signing algorithms.

Quickly check the exp and iat claims in human-readable form to confirm whether a token is still valid or has expired. No code needed.

Decode access tokens and ID tokens from OAuth2 and OIDC flows to verify scopes, nonce, and identity claims during integration testing with providers like Auth0, Okta, or Keycloak.