JWT Debugger
Decode and inspect JSON Web Tokens (JWT) headers, claims, and verify expiration dates safely in browser.
Your files are processed in your browser and are not uploaded to our server.
Encoded Token
Tokens are decoded 100% inside your browser. No data is ever transmitted over the network.
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How to Use JWT Debugger
1
Paste Token
Paste your encoded JWT string into the input box.
2
Inspect Claims
Review decoded header parameters, payload claims, and signature.
3
Check Expiration
See whether the token is currently active or expired.
Key Features
100% private client-side decoding (tokens never touch a backend)
Automatic exp/iat/nbf timestamp human-readable translation
Active / Expired validity badge status
One-click formatted JSON copy for header and payload
Frequently Asked Questions
Everything you need to know about this tool and data privacy.
Yes! All decoding is executed strictly in your browser JavaScript memory with no server calls or analytics logging.
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