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STC Software Module

The STC "software module" is a binary library designed to run on a Windows server.  It comes with several different interfaces from which you can choose the best to suit your needs:

  1. an ITaxCalc "DCOM object" (a DLL—view the ITaxCalc Interface);
  2. a simple interface (the same DLL), callable from any language running on a Microsoft operating system, including Excel;
  3. a command-line interface whose output can be redirected.
This is not a stand-alone software package.  It is intended to be integrated into your existing business system via custom programming to automate lookups of general sales tax rates by ZIP code.  If you have purchased your business system from someone else, have them contact us to find out how easy it is to integrate our interface.

System Requirements

  • Windows XP or 2000 or later
    -- or --
    SCO, Linux, Solaris, BSD.
  • Internet connection via HTTP port 80

Programmer's Kit

After you Sign Up on our web site, we will be able to send you our programmer's kit for further evaluation.


Please refer back to our Services page.