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
List Datepicker
Add a Datepicker with calendar select to a column or multiple columns in a Gravity Forms List Field.
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.
Dynamic Labels
One form, different questions: field labels and texts come from another form's entry, such as a grant, vacancy or course.
Personal Edit Link
Let people correct their own Gravity Forms entries. Send a secure personal link that reopens the form with their saved answers and updates the original entry, with locked fields, audit history and optional Gravity Flow steps.
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