JWT Decoder
Decode a JSON Web Token to read its header and claims, see when it expires, and verify HS256/384/512 signatures with your secret.
Free · No upload · 100% on your device
How to use JWT Decoder
- Type or paste your code or data.
- Choose the settings in the side panel. The result updates as you type.
- Copy the result or download it as a file.
Private by design. Everything you type, open or record is processed in this browser tab and is never uploaded to KittySuite.
About JWT Decoder
Tokens are often live credentials, so decoding them on a website that sends them to a server is risky; here they stay in this tab. Dates such as exp and iat are shown in your time zone. Enter the secret to verify HS256, HS384 or HS512 signatures; RS and ES tokens need a public key and are decoded only.
Everything runs in this browser tab: your text is never uploaded or stored, and the result updates as you type. It keeps working offline once the page has loaded.
JWT Decoder: frequently asked questions
How do I decode a JWT?
Paste the token. The header and claims are shown as JSON, with dates such as exp and iat in your time zone.
Is it safe to paste a real token here?
The token stays in this browser tab and is not sent to a server. Tokens are often live credentials, so still treat them carefully.
Can I verify the signature?
Yes, for HS256, HS384 and HS512 tokens: enter the secret. RS and ES tokens need a public key and are decoded only.
How do I know if a token has expired?
The exp claim is shown as a date with whether it is already past.