Form Calculations

With the 123FormBuilder online form builder you can perform calculations on your web forms & surveys. Use form calculations to add mathematical operations between your form fields on your online forms. To create calculations on your form, add an input field such as a Number field or a Price field. This will return the value of your calculation formula. You can also add calculations between the Time and Date fields. The operation between two Time fields, for example, will return the value in number of minutes, while the one between Date fields will return the value in number of days. Go to the SettingsPayments -> Calculations section of your form and select the field in the dropdown list below Assign Values or Formulas to Fields.

form calculations

Select Formulas in Add Values or Formulas. A calculator will appear below where you can add operations between your form fields (Date, Time or numeric input fields). Use the dropdown list within the calculator to add your form fields. Once the field is selected, it will be automatically added in the formula. You can use your keyboard to add operators and values. In the end, press Save on top.

form calculations

Note: You don’t need to enable payments on your form in order to use form calculations. Form fields that have been assigned as formulas cannot be overwritten by form users.

Here’s an example above of an online form that calculates the number of days you have lived:

Olivian Stoica
Olivian Stoica
Oli's enthusiasm for helping our fellow users led him to write thorough know-how articles and tutorials that would make form building a bliss on 123FormBuilder.


  1. Heeyoung Yoon says:

    I need a functionality that turn off the dates before today,,, like the calendar used in hotel booking website.

    Thank you.

This website is using cookies. By continuing to browse, you are
agreeing to our use of cookies as explained in our Cookie Policy. OK