JWT Decoder
Free online JWT (JSON Web Token) decoder. Splits header, payload and signature, formats registered claims and shows expiry status. Parsed locally in your browser; signature is NOT verified or uploaded.
How to use
What it does
A JWT (JSON Web Token) is three parts joined by dots: header.payload.signature. This tool base64url-decodes the first two parts into readable JSON, converts time-based claims like exp, iat and nbf into human dates, and flags the expiry status.
Example
Paste this JWT:
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkRldlV0aWxzIiwiaWF0IjoxNzAwMDAwMDAwLCJleHAiOjE3MDAwMzYwMDB9.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5cYou'll get the header (alg / typ), the payload (sub / name / iat / exp) and the signature segment.
Important security note
⚠️ This tool decodes only, it does NOT verify the signature. Anyone can forge a header and payload locally, so the decoded content must never be trusted for authorization. Always verify the signature with your secret on the server.