freanki

This widget shows the time since a specific date. You can enter text before and after the result.
You have to enter the date like this: 2012-01-31, so it’s year-month-day.
Thats all 🙂

Time since date

This Plugin provides a widget which shows the days, weeks, month or years since a specific date.

Gravity Extra

Create a new custom field for “GravityForms” plugin called “Date/Time” field:
<ul>
<li>Add a new field called “Date/Time” field to GravityForms fields.</li>
<li>User can drag that field into the form and use it.</li>
<li>The field will allow user to select both Date and Time for one field.</li>
</ul>

Date/Time Fields for Gravity Forms

Create a new custom field for "GravityForms" plugin called "Date/Time" field.

Time since date vs Date/Time Fields for Gravity Forms