Formula

Overview

Make your form a math wiz by allowing it to perform calculations. You can total up costs, process grade quizzes, apply discounts, and more!

Use the Formula field to set up any form calculation. When your respondents fill in the form, calculations will be performed based on their input. The answer will be displayed in the field you have entered your formula in.

Using the Formula field you can,

Perform mathematical operations such as addition, subtraction, multiplication, and division
Use certain math functions to calculate differences between two times, dates, and more
Set up conditional calculations to perform calculations based on the respondent's answers

Setup

To add a formula field to your form,

Click the Formula field under the Number section.
In the pop-up, your form fields would appear in the left pane. Use the fields on the left, numbers, and mathematical operators on the right to come up with your formula.
Click Done.
You can choose to hide this field from your respondents using the Hide Field option under Properties.
If you wish to edit your formula, click the Edit link under Properties .

Supported Field Types for Formula
Number, Decimal, Currency, Slider, Rating, Formula, Radio, Checkbox, Multiple Choice, Dropdown, Image Choice, Date, Date-Time, Time.

For example, you can calculate the amount your customer has to pay using the formula field and display the amount in the payment field automatically. For this, you can set the formula as Item * Quantity , where the number value assigned for the field Item is taken for the calculation.

Note :

While using the Formula field as a variable for calculating another formula, ensure that the two formulas are not mutually dependent. If you have come across an error because two formulas are mutually dependent, then refer to the below example:

If n1, n2, n3 are three number fields, and f1, f2, f3 are the formulas that you have created where,

f1= n1+ n2
f2= n3 + f3
f3= f1 + f2

Formula 2 depends on Formula 3's answer (and vice versa) to perform calculations, resulting in an endless loop. Recheck your formula to avoid this type of infinite loop.

Functions

Using the math functions we support, you can calculate the differences between time and date fields, and also round off decimal numbers into integers. You will find Functions in the right pane of the Formula field pop-up.

To use a function,

Tap on the math function you wish to add.
It generates a syntax like this: Function (Field Name - Field Name) .
Replace the field's placeholders with the required form fields by clicking them from the left pane.

Supported Math Functions

Function	Role	Supported Field Types
DayDiff	Returns the day difference between two date values	Date, Date-Time
MonthDiff	Returns the month difference between two date values	Date, Date-Time
YearDiff	Returns the year difference between two date values	Date, Date-Time
HourDiff	Returns the hour difference between two time values	Time, Date-Time
MinutesDiff	Returns the minute difference between two time values	Time, Date-Time
RoundUp	Rounds off the decimal number to that next value, away from zero	Decimal, Currency, Formula
RoundDown	Rounds off the decimal number to that of the previous value	Decimal, Currency, Formula
Round	Rounds off a decimal number to that of the next number when the decimal value is .5 or above, and to the previous number when the decimal value is below .5	Decimal, Currency, Formula

Learn more about other functions and their usage.

Adding a Unit to Formula

You can add a unit to your formula to show the result more contextually in the live form. A unit can be added once the formula configuration is completed.

To include a unit for the formula calculated value:

Enter a suitable Unit under Properties .
You can select to position this unit either as a Prefix or a Suffix.

Note : The unit for a formula will be displayed only in Subform's Pop-up mode.