Using Gravity Forms for Age Verification: How to set up Age-based Validation

Some forms need age-based restrictions attached to them. For example, an age verification form allowing entry to a site that advertises alcohol or cannabis can prevent submission if the user is below the minimum legal age.

In this tutorial, we’ll show you how to use GF Date Time Calculator to create a Gravity Forms age verification process to validate the user’s age and prevent submission based on that age. Let’s get started!

Getting Started

This tutorial will use GF Date Time Calculator to calculate the user’s age based on their birthdate. If the user’s age falls below a specified threshold, the submit button will be hidden and a validation message will display indicating why they can’t submit the form.

Steps

1. Add a Date Field
2. Add a Number Field and Calculate Age
3. Add HTML Field and Set up Conditional Logic
4. Apply Conditional Logic to The Submit Button

Step 1 – Add a Date Field

Start by adding a Date field to the form. In this field, we’ll capture the user’s birth date, so give it an appropriate name like “Date of Birth”.

Step 2 – Add a Number Field and Calculate Age

Add a Number field to your form to calculate the user’s age. Enable calculation on the field and insert the merge tag for the “Date of Birth” field with the :age merge tag modifier to calculate age. Make sure to set the Date Calculation Unit to “Years”.

You should also set this field’s visibility to “Hidden” in the Advanced tab. It doesn’t need to be displayed to the user.

Step 3 – Add HTML Field and Set up Conditional Logic

With the age calculation handled, it’s time to create your validation message. Add an HTML field to the form and add your message. Enable Conditional Logic on the field and add rules to show the field if the user’s age is below (or above) your specified threshold.

Note that we also have a rule so the field only shows if the “Date of Birth” field is not blank. This prevents the validation message from displaying before the user has entered a date.

Step 4 – Apply Conditional Logic to The Submit Button

With the validation message sorted, the next step is to prevent form submissions if the Age is below the threshold. To do this, activate Conditional Logic on the Submit button and set the rules to match this screenshot.

This setting has the added benefit of preventing the Submit button from being active unless the user enters their Date of Birth.

Your age verification form is ready to go.

With everything set up, if a user enters a date of birth that is below our acceptable threshold, they’ll be shown a validation error and the Submit button will be hidden.

Alternate age verification methods using Gravity Forms

Age-based validation can also be accomplished using GF Conditional Logic Dates.

Instead of using a Number field to calculate the user’s age, we’re going to do everything inside of the HTML and Submit button’s Conditional Logic. The magic lies in Conditional Logic Dates’ {today} merge tag. It lets you compare the user inputted date with a relative date from today. In the case of my form, we’re going to use {today:-18 years} to prevent submissions for anyone younger than 18. Here’s how it looks for my HTML field:

Notice we’ve set the logic to “Date of Birth” is greater than {today:-18 years}. This will match any date value that is more recent than the relative date.

The Submit button Conditional Logic is set up similarly.

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