JWT Decoder
Decode and inspect JSON Web Tokens instantly. See header, payload, expiry status.
Paste a JWT above to decode header, payload, and signature.
What is a JWT?
A JSON Web Token (JWT) is a compact, URL-safe token format used for securely transmitting information between parties. It consists of three Base64url-encoded parts separated by dots: a header (algorithm and type), a payload (claims like user ID, roles, and expiry), and a signature.
How to use it
Paste a JWT string into the input area. The tool instantly splits it into its three parts and decodes the header and payload into readable JSON. It also checks the expiry claim and shows whether the token is still valid.
About signature verification
This tool decodes JWTs — it does not verify signatures. Signature verification requires the secret key or public key used to sign the token, which only the issuing server should have. Use this tool for debugging and inspection, not for security validation.
