JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I'm not sure what is the scope of the limitation, but if you are doing a calculation and the math function you are using is available in our end, it should still work.
You can check this guide on how to do a form calculation: http://www.jotform.com/help/259-How-to-perform-calculation-in-the-form.
For the list of Math Functions that is available, you can refer to this link: http://www.jotform.com/help/267-Form-Calculation-Math-Function-Reference
If you could provide us more details of how your formula or form works, that would help us better assist you.