This JWT decoder reads any JSON Web Token and shows you exactly what’s inside: the header, the payload, and when the token expires. Paste a token below and it decodes instantly, right in your browser. Nothing you paste here is sent to our server, logged, or stored.
What This JWT Decoder Actually Shows You
A JWT is not encrypted, it’s encoded. Anyone who has the token, including a tool like this one, can read the header and payload without knowing the secret key used to sign it. That’s expected behavior under the JWT specification, RFC 7519, not a flaw in this tool. The signature is what proves the token hasn’t been tampered with, and this tool deliberately does not attempt to verify it, since that would require the issuing server’s secret key, which no legitimate client-side tool should ever ask you for.
🔒 This runs entirely in your browser. Your token is never sent to our server or stored anywhere.
The most common reason to decode a JWT is a login that mysteriously stops working. If the “exp” claim in the payload has already passed, that’s usually the answer: the token expired and the application didn’t refresh it. This tool flags that automatically instead of making you do the date math yourself.
⚠️ Never Paste a Production Token You Don’t Trust the Tool With
This particular tool runs entirely client-side and never transmits what you paste, but that’s not true of every JWT decoder online. As a habit, avoid pasting real tokens from production systems, especially ones tied to sensitive accounts, into any tool without confirming it doesn’t send data anywhere first.
If you work with authentication systems more broadly, our guide on how 802.1X authentication works and our login security checklist cover the surrounding pieces this token is usually part of.