What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No signup required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
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.

Calculate field option and Sum function in calculation wizard
Asked by businet on May 17, 2014 at 10:33 PM 
JotForm Support
Hi,
The calculation feature is moved as a Widget to our widgets section. Please check this guide: https://www.jotform.com/help/259Howtoperformcalculationintheform
Let me also add that if you have a field, for example, a dropdown field, each option can have a calculation values. You just need to set it into the field properties. Please check this screenshot:
Settings > Show Properties > Calculate Values:
This feature in each field is useful if you want to hide the prices and just show the text options.
Also check this related guides for calculation:
https://www.jotform.com/help/267FormCalculationMathFunctionReference
https://www.jotform.com/help/270HowtoPassaCalculatedValueinaPaypalFieldofaSecondForm
Hope that helps. Let us know if you have any further questions.
Thanks

JotForm Support
This thread is currently marked as notanswered, but we do not receive your reply. Please access this thread and respond from here instead: http://www.jotform.com/answers/378913.
Thanks

Thanks but all I am looking for is a simple 'Sum' function. I do not think it is in the list?

JotForm Support
@businet
Hi, you meant the "Sum function" was not available in the Math Function Reference right?
To have SUM() using the Calculation widget, you just use addition function.
Basic math operators like (add, multiply, division and subtraction) were already available. I think most of those listed in the math reference were advance math functions instead.
Hope this help. Please inform us if you have further question.
Thanks!

Thanks I have used this function. But I have 18 different questions. It would have been easier if I just put in 'sum(Q1.Q18)'. The Sum function is a standard mathematical function available say in Excel but not the JotForm Math Function Reference. i just find this strange when there are many other, often not used, functions there.

Hello businet,
The Sum function of excel won't work perfectly for forms unlike spreadsheets. Spreadsheet cells has a constant cell address which you can reference to sum up their values. Forms on the other hand are fields of different types and their labels vary from time to time.
Should you wish to use a spreadsheet to calculate values, you may wanna consider using the Spreadsheet widget which can use formulas to calculate the values.
Bryan