Duration math
Add or subtract time durations without manually carrying 60 minutes into the next hour.
Duration math
Time durations do not behave like normal decimal numbers because 60 minutes make one hour. For example, 7 hours 45 minutes plus 2 hours 30 minutes equals 10 hours 15 minutes—not 9 hours 75 minutes. This calculator converts both durations to minutes, performs the addition or subtraction, and then converts the result back to normalized hours and minutes. It also shows the same result as decimal hours and total minutes.
Use duration math when totaling work blocks, combining task times, checking a timesheet, adding travel time, or subtracting a break from a known duration. You can enter minutes greater than 59 if that is how your source data is written; the result is normalized automatically. If your starting information is a clock-in and clock-out time instead of a duration, use the Time Calculator or Time Card Calculator so overnight shifts and breaks are handled correctly.
Yes. The calculator normalizes the total automatically, so 90 minutes is treated as 1 hour 30 minutes.
Yes. Choose Subtract. If the second duration is larger than the first, the result is limited to zero rather than showing a negative duration.
This page calculates durations. Use the Time Calculator when you want the time between clock times or need to add hours to a specific time of day.