Calculate actual working time between a start and end time, subtract breaks and handle shifts that cross midnight.
Calculating work hours looks easy when a day starts at 9:00 and ends at 17:00. It becomes more error-prone when you need to subtract lunch breaks, combine schedules or handle a shift ending after midnight.
The reliable method is to separate three values: start time, end time and total unpaid breaks. Actual working time is the elapsed duration minus the breaks that should not count as work.
For a day that does not cross midnight:
working time = end time - start time - breaks
Example: start at 8:30, finish at 17:15 and take a 45-minute break. The elapsed time is 8 h 45 min; after subtracting the break, the result is 8 hours.
Thirty minutes is half an hour, so 7 h 30 = 7.5 hours. Likewise, 15 minutes = 0.25 hour and 45 minutes = 0.75 hour. This matters when adding durations in spreadsheets or reports. Bethemesh’s duration converter can convert minutes to hours and back.
Only subtract a break when it is not counted as working time. A 9:00–18:00 presence period with a one-hour break represents 8 working hours. If there are several breaks, add them first and subtract their total.
The work hours calculator accepts a start time, end time and break duration directly.
A shift from 22:00 to 06:00 is not negative: it lasts 8 hours. With a 30-minute break, actual working time is 7 h 30 min. A suitable calculator must treat an earlier end time as potentially belonging to the following day.
Presence time is the full interval between arrival and departure. Working time can be shorter after breaks are removed. The time duration calculator measures the raw interval, while the work hours calculator includes break handling.
For multiple days, converting each duration to minutes before adding them is often easiest. For example, 7 h 45, 8 h 10 and 6 h 30 equal 465 + 490 + 390 = 1,345 minutes, or 22 h 25 min.
Work-hour calculations run directly in your browser. The schedules you enter do not need to be sent to Bethemesh.
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