Understanding your calculation
Method, example and limitations
How the calculation works
Date arithmetic adds or subtracts calendar units or counts the interval between dates. Review whether the start and end dates are included.
Example to check
From January 1 to January 2 is one elapsed day. Counting both calendar dates as included gives two dates.
Before using the result
Months have different lengths and leap years affect February. A calendar date calculation is not automatically an elapsed-time calculation across time zones.