HMAC Generator

使用方法

1. Enter the message you want to authenticate in the message field。
2. Enter the secret key in the key field。
3. Select the algorithm: SHA-256, SHA-384, or SHA-512。
4. Copy the hexadecimal HMAC digest from the output。
5. All computation runs in your browser via the WebCrypto API — nothing is stored or sent anywhere。

範例

• Message "GET /api/data" with key "mysecret" and SHA-256 produces a 64-character hex digest used to verify the request signature。
• Changing a single character in the message or key produces a completely different digest, confirming tamper detection。