HMAC SHA-256 Signature Generator
When building secure APIs, webhooks, or payment integrations (like Stripe or GitHub webhooks), you need a way to prove that the payload was not tampered with in transit. Our HMAC Generator uses the industry-standard Hash-based Message Authentication Code algorithm with SHA-256 to create cryptographic signatures securely.
How does HMAC work?
Unlike a standard SHA-256 hash which anyone can compute, an HMAC combines the payload message with a Secret Key known only to the sender and receiver. If a malicious actor intercepts the payload and alters it, the receiving server will compute a different HMAC and reject the request.
100% Privacy and Security
Your Secret Key is the literal key to your application's security. Entering it into a standard online tool is a massive risk. Our application solves this by performing the HMAC encryption entirely locally within your browser using JavaScript cryptography. The secret key never leaves your machine.