Secure HMAC Signature Generator Online
Generate HMAC-SHA256 and HMAC-SHA512 signatures locally in your browser.
What is an HMAC Generator?
Hash-based Message Authentication Code (HMAC) is a specific type of message authentication code (MAC) involving a cryptographic hash function and a secret cryptographic key. An HMAC generator online allows you to verify both the data integrity and the authenticity of a message simultaneously. By using a secret key, HMACs ensure that a message cannot be modified by an attacker without the key, making them more secure against certain types of attacks than simple hashing. It is a fundamental component of secure API authentication and webhooks.
When should you use HMAC?
HMACs are widely used in protocols like IPsec, SSH, and for securing communication with APIs (such as Amazon Web Services or Stripe). You should use this free online tool to generate or verify signatures when testing your API integrations or implementing secure messaging. It supports algorithms like HMAC-SHA256 and HMAC-SHA512 for maximum compatibility. To ensure your secret keys remain secret, Cipherly never sends your key or message to a server. Everything is calculated locally using the Web Crypto API, maintaining a zero-knowledge environment for your most sensitive cryptographic keys.