Calculate Clock-Out Time Across Midnight
Treat the finish as a timestamp on the next day, not just a smaller number on the clock. That single detail removes most night-shift mistakes.
Overnight shifts are ordinary duration calculations with a date change in the middle. If a shift starts at 10:00 PM and lasts 8 hours plus a 30-minute unpaid break, the result is 6:30 AM tomorrow.
The reliable way to cross midnight
- Keep the start date attached to the clock-in time.
- Add required work and unpaid breaks as a duration.
- When the total passes midnight, advance the calendar date.
- Display “tomorrow” or the exact date beside the finish time.
Three night-shift examples
Calculating hours already worked across midnight
If you know both timestamps, subtract the start from the next-day end. For example, 10:00 PM to 6:30 AM is an 8-hour 30-minute span. Subtracting a 30-minute unpaid break leaves 8 paid hours. The Work Hours Calculator handles this automatically when the end time is earlier on the clock.
Daylight-saving time needs the real date
A shift that crosses a daylight-saving transition may not match the apparent difference between wall-clock times. One hour can repeat or disappear. For those dates, use the actual local date and timezone recorded by the workplace system rather than assuming every night is exactly 24 hours.
Avoid these night-shift mistakes
- Do not treat 6:00 AM as earlier than a 10:00 PM start.
- Do not omit “tomorrow” from a result shared with someone else.
- Do not add a paid break again to the planned finish time.
- Do not use a generic 24-hour assumption on a DST transition.