Download of Hex Calculator 10.1 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this free software for Mac is Softlibs. The software lies within Productivity Tools, more precisely Calculators. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe.
From the developer:
Hex Calculator provides six hexadecimal conversions for scientific computing. This scientific calculator supports BIT-2 (Binary), BIT-4, BIT-8 (Octonary), BIT-10 (Decimal), BIT-16 (Hexadecimal), and BIT-32 conversion. The program has a straightforward interface that makes using the application a simple task.
You may want to check out more software for Mac, such as Hex Fiend, CI Hex Viewer or Hexen II, which might be related to Hex Calculator.