Quick answer
Subtract the start from the end after placing both on the same timeline. For an end on the next day, add 24 hours to the end before subtracting.
Step by step
- Convert each clock to minutes after midnight. For example, 06:15 is 6 × 60 + 15 = 375 minutes.
- Add 1,440 minutes to the end only if it is on the following day. If the end is earlier and you selected the same day, check the inputs.
- Subtract start minutes from end minutes. Divide by 60 to get whole hours and retain the remainder as minutes.
Worked examples
Cross midnight
22:30 to 06:15 next day is (375 + 1,440) − 1,350 = 465 minutes, or 7 hours 45 minutes.
Stay on one day
09:20 to 11:05 gives 105 minutes, or 1 hour 45 minutes.
Equal readings
08:00 to 08:00 on the same day gives zero. With an explicit next-day end, the interval is 24 hours.
What to check
The two clocks alone cannot tell you which dates they belong to. Confirm the end day before subtracting. If you need a net shift total, subtract unpaid breaks after calculating elapsed time.
Related guides
Sources
See the calculation methodology or report an error.