How to calculate the age based on date of birth entered by the user?

You can use the DIFF function to calculate the age based on the date of birth entered by the user.

You can use the DIFF function to calculate the age based on the date of birth entered by the user.

Instructions to calculate age

Step 1: Add a short answer question in Google Forms.
Step 2: Click on the Addon icon > Select Formfacade > Select Customize this form > Click on the Proceed button.
In the Formfacade customize interface, click on the ⚙️icon next to the short answer question for age.
Step 3: Field settings screen will be displayed. Select the "Answer" tab and write the formula to calculate the age.

Use DIFF and TODAY function to calculate age

Diff function calculates the number of seconds, minutes, hours, days, months or years between two date or date & time questions. Since we want to calculate the age, we will use years as the unit.

TODAY().diff(date_of_birth, "years")

Note: To enter date_of_birth, type @ in the calculate option and select the date of birth question from the list.

Step 4: Write the formula in the Calculate option for age question as shown below.