Tools › JWT Decoder
JWT Decoder
Decode a JWT header and payload online. See algorithm, issued and expiry times and whether it has expired. Runs in your browser; nothing is uploaded.
Use it from code
The same function is available as an API endpoint. Free tier: 100 calls per day without a key. Pro lifts the limit.
curl -X POST https://spincrus.uz/api/v1/tools/jwt-decoder \
-H "content-type: application/json" \
-H "x-api-key: YOUR_KEY" \
-d '{"token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"}'FAQ
Does this verify the JWT signature?
No. It only decodes the header and payload, which are base64url-encoded JSON, not encrypted. Verifying a signature requires the secret or public key and is out of scope for a client-side viewer.
Is my token uploaded anywhere?
No. Decoding runs entirely in your browser using JavaScript; the token never leaves your device.
Why does the decoder say my token is expired?
The payload's "exp" claim is a Unix timestamp in seconds. If it is earlier than the current time, the token is expired and most servers will reject it.
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