JWT Decoder

Free Online JWT Token Decoder

Decode and inspect JSON Web Tokens (JWT) instantly. See the header, payload, and signature in a structured, readable format — perfect for debugging authentication flows.

What Is a JWT?

A JSON Web Token (JWT) is a compact, URL-safe token format used for authentication and information exchange. It consists of three Base64URL-encoded parts: a header (algorithm and type), a payload (claims), and a signature.

Recognized Claims

The tool automatically identifies standard claims like iss (issuer), sub (subject), aud (audience), exp (expiration), nbf (not before), iat (issued at), and jti (JWT ID), and displays them with human-readable descriptions.

Security Note

This tool only decodes JWTs — it does not verify signatures. All decoding happens in your browser; your tokens are never sent to any server.