Do you want to calculate how many hours there are in between different Time Fields? Or days or years in between two different Date Fields? With the Gravity Forms Date Time Calculator Add-on from Gravity Perks you can easily do that.
Calculating seconds, minutes, hours in between Time Fields
The Add-on adds extra Merge Tags that are availabe for Number Field calculations. In this example we’ve added the End Time Merge Tag and substracted the Start Time Merge Tag.

Once you add a Time Field Merge Tag to your calculations, an extra dropdown comes available to pick how you want to show the result: Seconds, Minutes, Hours, Days, Weeks, Months, Years.

Calculating days, months, years in between Date Fields
With the same approach you can calculate the difference in between Gravity Forms Date Fields:

Rounding minutes, hours, days, months, years
With the Advanced Number Field Add-on you can easily round the calculation result.

You can also add a Custom Unit to the calculation Number Field (like hours, days):

Which will result in:

Our Premium add-ons for Gravity Forms
API Connector
Connect Gravity Forms to External API's: Query the API using form field values and automatically fill other form fields with the API response.
Entry to Database
Integrates Gravity Forms with internal or external databases, offering flexible mapping of form fields to database columns and real-time synchronization between entries and database rows.
List Dropdown
Add a Dropdown Select with choices to a column or multiple columns in a Gravity Forms List Field.
Update Multiple Entries
Trigger the update of multiple entries in a target form by submitting an entry in a trigger form.
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