JWT Decoder
Decode and inspect JWT header and payload locally.
JWT Decoder splits a JSON Web Token into header, payload, and signature segments and pretty-prints the JSON. It does not verify signatures — use it to inspect claims while debugging. Tokens never leave your device.
Frequently Asked Questions
Does my text leave the browser?
No. This tool runs entirely in your browser. Nothing is uploaded to our servers.
Does this verify the signature?
No. It only decodes Base64url segments. Signature verification needs your secret or public key elsewhere.
Is it safe to paste production tokens?
Decoding is local, but avoid sharing tokens that grant access. Treat JWTs like passwords.