Use this time and date duration calculator to find out the number of days, hours, minutes, and seconds between the times on two different dates. To add or subtract time from a date, use the Time Calculator.

Calculating the duration between two times can be a little tricky depending on the numbers of minutes and seconds in the two times being compared. As an example, the following are the steps to determine the number of hours and minutes between two chosen times within the same day:

First, identify the starting and an ending time. The goal is to subtract the starting time from the ending time under the correct conditions.

If the times are not already in 24-hour time, convert them to 24-hour time. AM hours are the same in both 12-hour and 24-hour time. For PM hours, add 12 to the number to convert it to 24-hour time. For example, 1:00 PM would be 13:00 in 24-hour time.

Determine whether the number of minutes is larger in the starting time or the ending time.

If the ending time has a larger number of minutes: Subtract the starting time from the ending time as you would subtract normally, keeping the hours and minutes on the appropriate side of the ":", where hours are on the left, and minutes are on the right. For example:

13:57

–

9:22

4:35

If the starting time has a larger number of minutes: Treat the hour and minute portion separately. Add 60 to the number of minutes in the ending time, and subtract 1 hour from the hour portion of the ending time. Then, subtract the minutes and the hours, keeping the result on the appropriate side of the ":" where hours are on the left, and minutes are on the right. For example: