JWT Decoder

A JSON Web Token (JWT) is a compact, URL-safe token used to securely transmit information between parties. It consists of three Base64-encoded parts separated by dots: header, payload, and signature.

Paste your JWT token into the input field. The tool instantly decodes and displays the header (algorithm and token type), payload (claims like user ID, expiry, roles), and signature.

Decoding happens entirely in your browser — your token is never sent to any server. However, avoid pasting tokens from production systems in public or shared environments as JWTs may contain sensitive claims.

No. Signature verification requires the secret key or public key used to sign the token. This tool only decodes the token to show its contents — it does not validate the signature.

The exp (expiration time) claim is a Unix timestamp indicating when the token expires. This tool automatically checks the exp value and shows whether the token is still valid or has expired.