Security & Identity
JWT Decoder & Inspector
Decode and inspect compact JWT or JWS headers, payloads, claims, and signatures locally in your browser.
How to use this JWT inspector
Paste a compact JWT or JWS to split and decode its Header, Payload, and Signature locally. exp, nbf, and iat are checked against the current time; confirm a token’s source before copying it elsewhere.
Time claims
exp is the expiration time, nbf is the not-before time, and iat is the issued-at time; all use Unix seconds (NumericDate). The tool rejects wrong types, non-finite values, and numbers that could lose precision.
Frequently asked questions
Can I trust the decoded result?
No. Anyone can create or modify an unverified token; this tool does not verify signatures, keys, issuer, or audience. Use a trusted server-side key to verify it.
What is the difference between JWT and JWS?
A JWT is commonly a JSON claims set represented as a JWS. This tool accepts compact three-part input and shows signature bytes, but it never verifies the signature.