Also available in the Chrome extension Every Zase tool also lives in the free Developer Toolkit by Zase extension: fully offline, in a window or the side panel, one keyboard shortcut away.
Add to Chrome
About this JWT Decoder
The JWT Decoder splits a JSON Web Token into its header and payload and shows the claims in a readable form, including the issued and expiry times. Reach for it when an API answers 401 and you need to see which user, scopes and expiry the token actually carries, instead of guessing.
How to use the JWT Decoder
- Paste the full token into the input field.
- Read the decoded header and payload panels, with claims laid out one per line.
- Check the expiry and issued-at claims against your clock before you blame the server.
Good to know
- Decoding is not verifying: this tool shows what a token says, it cannot prove who signed it.
- Never paste production tokens into online decoders that send them to a server; here the token stays in your tab.
- Pairs well with the JWT Signer when you need to create a matching test token.