How to work it out by hand
- Convert both times to 24-hour format: 5:15 PM is 17:15.
- Subtract the start from the end. If the minutes go negative, borrow an hour: 17:15 − 8:45 → 16:75 − 8:45 = 8:30.
- If the end is earlier than the start, add 24 hours to the end first.
- Subtract any unpaid break.
Decimal hours
Payroll usually wants decimal hours. Divide the minutes by 60: 8 hours 30 minutes is 8.5 hours, 8 hours 20 minutes is about 8.33.
Frequently asked questions
How many hours is 9 AM to 5 PM?
8 hours. With a 30-minute unpaid lunch it is 7.5 hours.
How many hours is 7 PM to 7 AM?
12 hours — the end is earlier than the start, so it runs past midnight.
Last reviewed 2026-10-14.