Print this page

Why is my formula to calculate the time between two date/time fields off by an hour?

Knowledge Article Number 000170892
Description I have created a formula which calculates the time between 2 date/time fields, however it is calculating a result 1 hour higher (or lower) than expected.
Resolution This could be an expected behavior if one of the date/times is during Daylight Savings, and the other date/time is not.

For example, the time from 12:00 AM to 1:00 AM on the day when DST ends is actually 2 hours, not 1 hour -- so if the "start date" was during DST, and the "end date" is after DST, the formula result will have an "extra" hour.

You will see a similar behavior when DST begins -- when DST goes into effect, clocks skip forward an hour and so your formula total will 'lose' an hour if the start is before DST and the end is during DST (e.g. when DST starts, clocks jump forward from 1:00 AM to 2:00 AM, so 12:00 AM to 2:00 AM is really only 1 hour on that date).

promote demote