HMAC Generator: SHA-256, SHA-384, and SHA-512 Digests
The HMAC Generator computes a keyed-hash message authentication code from your text and shared secret using the browser's native WebCrypto. Choose SHA-256, SHA-384, or SHA-512, then get the same digest represented in hex and Base64. Use these outputs to sign API requests or support message-integrity checks; the selected algorithm and secret determine the result.
HMAC Generator is a browser-based tool for creating a keyed-hash message authentication code from text and a shared secret. As an HMAC generator online, it uses the browser's native WebCrypto and offers SHA-256, SHA-384, and SHA-512. The result is available as both a hex digest and a Base64 digest, making it useful when developing API request signatures or working with message-integrity checks.
To generate an HMAC, enter the message and shared secret, then select the hash algorithm. The selected algorithm and the input values determine the resulting digest. This HMAC-SHA256 generator also supports SHA-384 and SHA-512, so you can choose the algorithm used by your application or workflow. Hex and Base64 are two representations of the generated digest; choose the one your task requires.
HMAC uses a secret key together with a hash algorithm to produce a message authentication code. XML, JSON, and other data formats are not part of this tool's conversion process: it takes text as input and returns an HMAC digest. Developers commonly need these values when preparing API request signatures, creating test fixtures, or working with message-integrity checks.
The tool runs entirely in your browser, and your input is not uploaded, stored, or sent to a server. It has no server dependency, so after the page has loaded, it continues to work offline. Developers and DevOps engineers can use it to generate and copy HMAC output without moving their input to another service.
Step 1: Enter the text you want to process. This message is used with your shared secret to create the HMAC.
Step 2: Enter the shared secret used by your application or service. The digest is calculated from both the text and this key.
Step 3: Choose SHA-256, SHA-384, or SHA-512. This setting selects the hash algorithm used to generate the HMAC.
Step 4: Generate the HMAC and review the result. The tool provides the digest in both hex and Base64.
Step 5: Copy the representation you need. Use hex or Base64 according to the format expected by your API request, test, or other workflow.
Use case: Create HMAC values for tests, fixtures, or seed data. Generate a digest from the same text, shared secret, and algorithm your test scenario uses.
Use case: Prepare an HMAC value for an API request. Choose the algorithm and output format expected by the service you are working with.
Use case: Support message-integrity checks in a development workflow. Generate a digest with the relevant shared secret and use it in your own checking process.
Use case: Create sample HMAC-SHA256 values while developing or debugging an implementation. Comparing outputs can help you investigate differences in message, key, or algorithm.
Use case: Get a digest in hex when that is the representation your code or documentation expects. The tool also provides Base64 if that format is more useful for your task.
Use case: Generate HMAC values for technical documentation or examples. Use a chosen message and secret to produce concrete hex and Base64 output.