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    How to have a unique formula on my form

    Asked by BradshawChristian on March 06, 2017 at 05:18 PM


    I am creating a payment form and I want to do a unique formula setup for it. I'd like to have the following in my form:

    Field 1 (typed in): An numerical amount typed in by the person completing the form.

    Field 2 (Derived, not keyed in): A "surcharge" amount that is derived by multiplying Field 1 by 2.98% 

    Field 3 (Derived, not keyed in): A total that adds Field 1 and 2 together, used to be the amount charged to the payment processor.


    Is this possible? If so, how could I do that? 



    Alicia Eastvold


    916-688-0521 *353

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    JotForm Support

    Answered by jonathan on March 06, 2017 at 07:35 PM

    You can achieve this using Calculation widget on you form.



    You can test my demo form below.

    test form: https://form.jotform.com/70647179658976

    Let us know if you need further assistance.