JWT Decoder
Inspect a JSON Web Token header and payload without sending the token to a server.
Decode only; the signature is not verified.
How the JWT decoder works
Paste a JWT
Add a JSON Web Token, made up of three dot-separated parts, into the input field.
Decode
The tool Base64URL-decodes the header and payload segments and displays each as formatted JSON.
Review the claims
Inspect the header and payload to check claims such as issuer, expiry or subject during debugging.
Frequently asked questions
Does this verify the token's signature?
No. This tool only decodes the header and payload for inspection; it does not verify the signature, so a decoded token should not be treated as validated or trustworthy.
Is my token sent to a server?
No. Decoding happens entirely locally in your browser using standard Base64URL decoding.
Why does decoding fail on my token?
A JWT must have exactly three dot-separated segments; if a token is truncated, has extra whitespace, or isn't a JWT, decoding will fail.