Signature is not verified. This tool only Base64URL-decodes the header and payload for inspection. Do not trust token contents for authorization without validating the signature with your issuer's secret or public key.
About this tool
What is the JWT Decoder?
The Wansify JWT Decoder reads a JSON Web Token in your browser, shows the header and payload as JSON, lists standard claims, and highlights whether the token is expired. It does not verify signatures.
How to use it
- 1Paste a JWT (three Base64URL segments separated by dots).
- 2Read the decoded header and payload panels.
- 3Check claims such as iss, sub, aud, iat, nbf and exp, including expiry status.
- 4Copy the header or payload JSON for debugging.
Features
- Decode JWT header and payload instantly
- Pretty-printed JSON for both parts
- Readable timestamps for iat, nbf and exp
- Expired, not-yet-valid and time-remaining status
- Algorithm and token type from the header
- Copy header, payload or raw segments
- Signature shown as opaque (not verified)
- Token never leaves your browser
FAQ
Common questions about the JWT Decoder
Does this tool verify the JWT signature?
No. It only decodes the Base64URL header and payload so you can inspect claims. Signature verification needs the signing secret or public key on a trusted server.
Is it safe to paste a JWT here?
Decoding runs only in your browser. Still avoid pasting production tokens into shared machines, and never share tokens that grant access to real systems.
What does an expired JWT mean?
If the exp claim is in the past, APIs that check expiry should reject the token. This tool shows that status from the claim; it does not contact your API.
Is my JWT uploaded to a server?
No. The tool runs entirely in your browser, so nothing you enter or upload is sent to a Wansify server.
Is the JWT decoder free?
Yes. It is free to use with no sign-up.
More free tools
Need something built?