JWT header and payload decoder
ReadyDecode a JWT header and payload; read-only, the signature, issuer and permissions are NOT verified. No secret key needed. Runs in this browser, the token never reaches a server.
All tools are free to use. File size and processing limits may vary by tool.
How to use
Paste the token and decode it; read the expiry and scope fields. A valid signature needs separate verification; this tool only reveals the content.
Browser tools keep files on your device. Advanced document tools upload files for temporary server processing; the tool shows this before upload. Web lookups send queries to the server and public lookup services.
JWT Header and Payload Decoder
Received a JWT from an API and want to inspect it? This decoder converts Base64Url sections into readable text in your browser. Review expiry, user ID and roles during development. Limit: it only decodes, it does NOT verify the signature.
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