JSON Web Token (JWT) Tool

Decode, verify, and forge JWTs directly in your browser. No data is sent to external servers.

Encoded Token

Paste a JWT here to decode it.

Decoded Data

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What is a JSON Web Token (JWT)?

A JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. This information can be verified and trusted because it is digitally signed. JWTs can be signed using a secret (with the HMAC algorithm) or a public/private key pair using RSA or ECDSA.

Frequently Asked Questions

Is it safe to decode JWTs here?

Yes. Our JWT decoder runs 100% locally in your web browser using JavaScript. Your tokens and secrets are never transmitted to any server.

Why does my signature verification fail?

Signature verification usually fails if the payload or header was modified, if you provided the wrong secret key, or if the token uses an unsupported algorithm (this tool currently supports HS256).