JWT Decoder

JWT Decoder reads the header and payload of a JSON Web Token and shows them as formatted JSON, without needing the signing key.

Use this when debugging why an API call with a JWT is behaving unexpectedly and you want to see exactly what claims it actually contains, or when learning how a specific service structures its tokens.

This only decodes the token, it does not verify the signature. Decoding a JWT without the key is normal and expected, that is how JWTs are designed to work; verifying one requires the issuer's signing key, which this tool never has.