HMAC Generator

Generate HMAC (Hash-based Message Authentication Code) signatures for any message and secret key. Supports HMAC-SHA1, HMAC-SHA256, HMAC-SHA384, and HMAC-SHA512 using the browser Web Crypto API. Output in hex or Base64. Essential for verifying Stripe and GitHub webhook signatures, signing API requests, and validating data integrity.

Why choose HMAC Generator?

The HMAC Generator provides a quick, browser-based solution for producing cryptographic signatures using the Web Crypto API without requiring server-side execution. It supports standard hashing algorithms like HMAC-SHA256 and HMAC-SHA512 with hex or Base64 outputs, keeping sensitive secret keys and messages within your local environment. Being entirely free and accessible without signups makes it well-suited for everyday development and testing tasks.

Good to know: For automated CI/CD pipelines or handling extremely large datasets requiring programmatic execution, a command-line utility or dedicated backend library may be more appropriate.

How to Use HMAC Generator

Generate secure HMAC-SHA256 or HMAC-SHA512 signatures to verify webhooks and authenticate API requests.

1. 1

   Enter your message or payload

   Paste the raw text, JSON body, or message string you need to sign into the input field.

2. 2

   Input your secret key

   Provide the private secret key or signing secret provided by your API provider like Stripe or GitHub.

3. 3

   Select the hashing algorithm

   Choose the required algorithm such as HMAC-SHA256, HMAC-SHA512, or HMAC-SHA1 from the available options.

4. 4

   Choose the output encoding format

   Select either Hexadecimal or Base64 encoding to match the format required by your specific integration.

5. 5

   Generate and copy the signature

   The tool automatically calculates the hash using the Web Crypto API; copy the resulting signature for your headers.

Estimated time: PT1M

Frequently Asked Questions

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HMAC Generator Guide: HMAC-SHA256 & SHA512 Signatures

Generate secure HMAC-SHA256 and HMAC-SHA512 signatures. Learn how to verify webhooks and sign API requests using our free, browser-based HMAC Generator tool.