How to work out the time between two times
Subtract the start time from the end time, then take off any unpaid break.
Time worked = end time − start time − unpaid break
For a shift from 9:00 AM to 5:30 PM with a 30-minute lunch: 9:00 AM to 5:30 PM is 8 hours 30 minutes, and minus the 30-minute break that leaves 8 hours, or 8.00 decimal hours.
When the minutes do not subtract cleanly
From 8:45 AM to 4:10 PM, the minutes (10 − 45) go negative. Borrow an hour: 4:10 PM becomes 3:70 PM. Then 3:70 − 8:45 in 24-hour time is 15:70 − 8:45 = 7 hours 25 minutes.
Overnight shifts
If the end time is earlier than the start time, the shift ended the next day. Add 24 hours to the end time before subtracting.
A shift from 10:00 PM to 6:15 AM: 6:15 AM the next day is 30:15 in running time, and 30:15 − 22:00 = 8 hours 15 minutes. This calculator does that automatically and tells you when a shift crosses midnight.
| Shift | Break | Time worked |
|---|---|---|
| 7:00 AM to 3:30 PM | 30 min | 8:00 (8.00 h) |
| 8:45 AM to 4:10 PM | none | 7:25 (7.42 h) |
| 3:00 PM to 11:30 PM | 30 min | 8:00 (8.00 h) |
| 10:00 PM to 6:15 AM | none | 8:15 (8.25 h) |
| 7:00 PM to 7:00 AM | 60 min | 11:00 (11.00 h) |
Which breaks to subtract
Only subtract breaks that are unpaid. Under federal rules:
- Short breaks of about 5 to 20 minutes count as paid work time. Leave them in. See 29 CFR 785.18.
- Meal periods, usually 30 minutes or more, are not work time when you are fully relieved of duties. Subtract them. See 29 CFR 785.19.
Federal law does not require employers to give breaks at all, but many states do. Check your state's rules and your employer's policy. The US Department of Labor summarizes the federal position on breaks and meal periods.
Turning the result into pay
Payroll multiplies decimal hours by your hourly rate, so the result also shows decimal hours. At $20 an hour, 8 hours 15 minutes is 8.25 × $20 = $165. To convert other times, use the hours to decimal calculator.