A shift crossing midnight needs one extra fact: whether its finish is on the following day. Two separate periods of work need separate rows. Making those choices explicit avoids silently turning a typing mistake into a long shift.
A shift across midnight
For a start at 22:00 and a finish at 06:00 the following day, the elapsed clock duration is eight hours. One way to check it is two hours before midnight plus six hours afterwards. Subtracting a 45-minute unpaid break leaves 7 hours 15 minutes, or 7.25 decimal hours.
Select Ends next day in the work-hours tool. Without that selection, an earlier finish is treated as something to check, not an automatic overnight assumption. Equal start and finish is zero elapsed hours; selecting next day makes it 24 hours before breaks.
Two shifts with a gap
Work from 08:00 to 12:00 is four hours. Work from 13:30 to 17:00 is three hours 30 minutes. The total is 7 hours 30 minutes. The 90-minute gap is not in either row, so subtracting it again would incorrectly reduce the total to six hours.
Use the same day on two rows of the time card. Enter an unpaid break only when it falls inside the clock interval of that row.
Why overlapping entries are rejected
An interval from 22:00 Monday to 06:00 Tuesday overlaps another starting at 05:30 Tuesday. Adding both intervals would count half an hour twice. Correct the recorded times before using the total. Two intervals that merely touch—one ends at 12:00 and the next starts at 12:00—do not overlap.
Week boundaries and changing clocks
The full duration of a Sunday-night shift is assigned to its starting week in this tool. It does not divide the shift into Sunday and Monday portions, nor does it calculate overtime. Use your workplace’s required allocation when preparing an official record.
These calculators use the clock times you type, without dates or time zones. On a night when clocks change, actual elapsed time can differ from that clock-time subtraction. Use dated records with the appropriate time zone for that case; do not treat the simplified answer as authoritative.
Planning a finish instead
For a 22:15 start, eight hours of required work and a 30-minute unpaid break, the clock-out calculator gives 06:45 next day. That is a planned finish from your assumptions, not permission to leave or proof of completed work.