JWT Decoder
100% PrivateDeveloper ToolsDecode a JSON Web Token and read its header and payload as plain JSON, with expiry times.
Runs entirely in your browser. Your input is not uploaded to Ovatly or anywhere else.
This tool only decodes the readable parts of the token. The signature is not verified, so a decoded payload is never proof that a token is genuine or trustworthy.
- 1Paste the full token (all three dot-separated parts).
- 2Read the decoded header, which names the algorithm and token type.
- 3Read the payload claims: subject, issuer, issued-at and expiry.
- 4Check the expiry panel for the verdict, and remember the signature warning.
The well-known demo token with header {"alg":"HS256","typ":"JWT"} decodes to a payload containing sub "1234567890", name "John Doe" and iat 1516239022. Add an exp claim of 4000000000 and the tool reports expiry on 2 October 2096, so the token is not expired. The signature segment is present but, as the page states, it is not verified.
- Decoding is not verification. Without the signing key or the issuer's public key, nobody can confirm a token is genuine, and this tool never claims to. A decoded payload is a claim, not a proof.
- Everything happens locally: tokens are credentials, so this page never uploads the one you paste.
- Tokens without an exp claim are reported as having no expiry of their own, which is common for some API tokens.
- Times are computed from the exp and iat claims, which are seconds since the Unix epoch.
No, and be suspicious of any decoder that implies it can. Verification needs the secret or public key used to sign the token, which a decoder page does not have. This tool decodes and labels the signature as not verified.
About this tool
The JWT Decoder shows you the header and payload inside a JSON Web Token, in plain JSON, with the expiry time translated into a readable date and a clear expired or not-expired verdict. Developers use it to debug authentication: checking which user a token claims to be, which issuer issued it, and whether it has already expired.
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Part of Ovatly's free tools in Developer Tools.