Build or verify signatures used by webhooks and APIs so you can debug integrations confidently.
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Frequently Asked Questions
HMAC (Hash-based Message Authentication Code) is a cryptographic method for verifying both the data integrity and authenticity of a message. It uses a secret key along with a hash function.
HMAC is commonly used for API authentication, webhook verification, and ensuring message integrity. It's used by services like AWS, GitHub webhooks, and many REST APIs.
SHA-256 is the most commonly used and recommended. SHA-512 provides stronger security but produces longer signatures. SHA-3 variants offer modern cryptographic properties.
Use the verify function with the original message, the signature to verify, and the same secret key and algorithm used to generate it. The tool will tell you if the signature is valid.
No, all processing happens in your browser. The secret key is never sent to our servers, ensuring complete privacy and security.