• This section is for upgrade from DiamCalc 2x to DiamCalc 3

  • You can find the registration key in DiamCalc by clicking on "Help" and then "About DiamCalc". Highlight and copy the serial no. and paste in the input box provided.
  • Octonus will verify your software key's validity and email you the link for secure credit card payment ( where you will provide your address and you will receive further instructions on downloading the DiamCalc file.