HMAC-SHA256 Hash Generator

HMAC is a message authentication code (MAC) using a hash function. It combines with any cryptographic hash function, for example, md5, sha1, sha256. Hash function is wrapped to a class as one template parameter in HMAC and the wrapper class only has a static function involving the hash function.

HMAC is more secure than any other authentication codes as it contains Hashing as well as MAC.

Below is a free online tool that can be used to generate HMAC authentication code. We can generate hmac-sha256 as well as hmac-sha512 code with it.

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We do not store, log any key you enter. This tool is intended for personal and educational use. We suggest not to use online tools to protect real production secrets.

HMAC (Hash-based Message Authentication Code) is a mechanism used for message authentication, which involves combining a cryptographic hash function with a secret key. It provides integrity and authenticity assurances for data, ensuring that the data has not been altered or tampered with by unauthorized parties.

How HMAC Works:

• Components:
  • Message:The data you want to authenticate.
  • Key:A secret key known only to the sender and the receiver.
  • Hash Function:Typically, a cryptographic hash function like SHA-256 or SHA-512.
• Calculation
  • Initialization:Choose an appropriate hash function (e.g., SHA-256) and a secret key K.
  • Key ModificationIf necessary, modify the key to fit the hash function's block size.
  • PaddingIf needed, pad the key so it fits the block size of the hash function. asymmetric algorithms.

Usage Guide - HMAC-SHA256 Online Tool

First, enter the plain-text and the cryptographic key to generate the code. Then, you can use select the hash function you want to apply for hashing. The default is SHA-256. Then you can submit your request by clicking on the compute hash button to generate the HMAC authentication code for you.

By default, the output is in plain-text format, but you also have an option to get the output in Base64 format. Below is a screenshot of the usage: