JWT Token Decoder - Free Online Tool

The JWT Token Decoder is a vital utility for developers working with modern authentication systems. It allows you to paste a JSON Web Token (JWT) and instantly see the decoded header and payload. This is essential for debugging authentication flows, verifying the contents of an ID token from an OAuth provider, or inspecting the claims (like user roles and permissions) embedded within a token. The tool does not validate the token's signature, as that requires a secret key; its purpose is to inspect the public parts of the token safely. It's a quick and secure way to look inside a JWT without sending sensitive tokens to a third-party server, as all decoding happens client-side.