Paste a JWT token below to decode its header and payload instantly. The tool validates the structure and displays claims in a readable format — no private key required.
JWT (JSON Web Token) is an open standard for securely transmitting information as a JSON object. A JWT has three Base64URL-encoded parts separated by dots: header (algorithm and type), payload (claims), and signature.
Paste your JWT token into the decoder above. The tool instantly splits it into header and payload, Base64URL-decodes each part, and displays the JSON content with syntax highlighting and claim annotations.
Yes. JWT decoding is safe because the header and payload are only Base64URL-encoded, not encrypted. This tool decodes entirely in your browser — no token data is ever sent to a server.
No. Signature verification requires the secret key (for HMAC algorithms like HS256) or the public key (for RSA/ECDSA). This tool only decodes the header and payload — it does not verify the signature.
The decoder annotates all standard JWT claims: iss (Issuer), sub (Subject), aud (Audience), exp (Expiration Time with valid/expired status), nbf (Not Before), iat (Issued At), and jti (JWT ID).