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JWT Decoder

Paste a JSON Web Token to read its header and claims.

This token does not leave your browser. The page has no network code, and the site's content security policy sets connect-src 'none', so it could not send the token anywhere even if it tried. The token is deliberately kept out of the URL as well, so it cannot end up in your history, a bookmark or a referrer header. A JWT usually is a live credential. Treat it like one.
Token
Three base64url segments separated by dots.
Waiting for a token
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Algorithm --
Claims 0
Header
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Payload
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Registered claims

On the signature The signature is shown but not verified. Verifying it requires the secret or public key that signed the token, and a decoded token proves nothing about authenticity on its own. Anyone can craft a token whose payload says whatever they like — only the signature check, done on your server against a key you control, makes it mean anything.