JWT Decoder
Paste a JSON Web Token to read its header and payload — decoded privately in your browser.
Header
Payload
Registered claims
Signature
Free online JWT decoder
The Ajenza JWT Decoder splits a JSON Web Token into its three parts — header, payload and signature — and Base64URL-decodes the first two so you can read the JSON. Standard time claims (exp, iat, nbf) are shown as readable dates, and the token is flagged as active or expired. Decoding happens entirely in your browser, so your token is never uploaded. Note that a JWT payload is only encoded, not encrypted — never put secrets in it, and always verify the signature on your server before trusting a token.
Is it free?
Yes — completely free, with no sign-up, download or watermark.
Does it check the signature?
No. It only decodes the header and payload. Verifying the signature needs your secret or public key and should be done server-side.
Is my token uploaded?
No — decoding runs entirely in your browser.
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