Is it safe to decode JWTs in the browser?

Yes. This tool decodes JWTs entirely client-side — your token never leaves your browser. However, remember that JWT payloads are only encoded, not encrypted, so never put sensitive secrets in a JWT payload.

JWT Decoder

Paste a JSON Web Token to decode and inspect its header, payload, and expiration. Decoding happens entirely in your browser — your token never leaves your machine.

JWT Token

Frequently Asked Questions

What is a JWT?

A JSON Web Token (JWT) is a compact, URL-safe token format used for securely transmitting information between parties as a JSON object. It consists of three Base64URL-encoded parts separated by dots: header, payload, and signature.

Is it safe to decode JWTs here?

Yes. This tool decodes JWTs entirely client-side — your token never leaves your browser. However, JWT payloads are only encoded, not encrypted, so never put sensitive secrets in a JWT payload.

What are common JWT claims?

Common registered claims include: iss (issuer), sub (subject), aud (audience), exp (expiration), nbf (not before), iat (issued at), and jti (JWT ID).