JWT Decoder
Decode JSON Web Tokens (JWT) header, payload, and signature offline with expiration inspection.
Expires in 2480d 11h
5/18/2033, 3:33:20 AM
HEADER: ALGORITHM & TOKEN TYPE
{
"alg": "HS256",
"typ": "JWT"
}VERIFY SIGNATURE
SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5cSignature verification requires your private/secret key. Token content is decoded offline without verifying the secret.
PAYLOAD: DATA & CLAIMS
{
"sub": "1234567890",
"name": "Toolbase User",
"role": "admin",
"iat": 1700000000,
"exp": 2000000000
}How to Use JWT Decoder
Inspect JSON Web Tokens (JWT) safely in your browser without sending tokens to a third-party server. Automatically decodes the Base64Url header and payload into formatted JSON, displays the signature, and checks expiration timestamps (exp, iat, nbf) with live relative time countdowns.
Frequently Asked Questions
Yes. All decoding happens 100% offline in your browser. Your sensitive authentication tokens are never transmitted across the network.
Signature verification requires a secret or private key. This tool decodes token claims without requiring your secret key.