InputTestHub

JWT Decoder

Decodes a JSON Web Token and shows the header, payload and claims in readable form, with expiry checking.

Developer Nothing uploaded No sign-up Free, unlimited
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In short JWT Decoder is a free online tool on inputtesthub.com that decodes a JSON Web Token and shows the header, payload and claims in readable form, with expiry checking. It needs no account, no download and no payment, and there is no daily usage limit. Everything is processed inside your own browser, so the data you paste is never uploaded to a server.

How to use the JWT Decoder

  1. Type or paste your input.
  2. The output is produced instantly as you type.
  3. Press Copy to take the result with you.

About the JWT Decoder

The JWT Decoder decodes a JSON Web Token and shows the header, payload and claims in readable form, with expiry checking. It runs as plain JavaScript inside the page, which means there is no upload step, no queue and no size limit imposed by a server — the only limit is your own device.

What people use it for

  • Checking what claims a token actually carries.
  • Seeing whether a token has expired and when.
  • Debugging an auth failure without adding logging.

Details

Sections decodedHeader, payload and signature (signature shown but not verified)
Time claimsiat, exp and nbf are converted to readable dates with a live expiry status
AlgorithmRead from the header and displayed, so you can spot an unexpected "none"
This decodes; it does not verify. A JWT signature can only be validated with the secret or public key, which should never be pasted into a web page. Treat a decoded token as untrusted until your server has verified it. Decoding happens entirely in your browser — the token is not transmitted.

Frequently asked questions

Is the JWT Decoder free?
It is free, with no account, no trial and no daily cap. Every developer tool on inputtesthub.com works the same way: open the page and use it.
Is my data uploaded anywhere?
No. The JWT Decoder runs entirely in your browser using JavaScript. Nothing is transmitted, logged or stored, which you can verify yourself in the Network tab of your browser's developer tools.
What do people use the JWT Decoder for most?
The most common reasons people reach for it: checking what claims a token actually carries. Seeing whether a token has expired and when. Debugging an auth failure without adding logging. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
Is there a catch?
This decodes; it does not verify. A JWT signature can only be validated with the secret or public key, which should never be pasted into a web page. Treat a decoded token as untrusted until your server has verified it. Decoding happens entirely in your browser — the token is not transmitted.
What figures does the JWT Decoder work from?
Sections decoded is Header, payload and signature (signature shown but not verified). Time claims is iat, exp and nbf are converted to readable dates with a live expiry status. Algorithm is Read from the header and displayed, so you can spot an unexpected "none". These are printed on the page itself, so you do not have to take them on trust.
Will this work on a tablet?
Yes. The page is responsive and the tool works in Chrome, Safari, Firefox, Edge and Samsung Internet on both Android and iOS. There is no app to install and nothing to sign into.

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