Time Duration Calculator
The duration between two times is the end time minus the start time: 8:30 AM to 5:45 PM is 9 hours 15 minutes. If the end time is earlier than the start time, the period crosses midnight and 24 hours are added.
Duration
8 h 45 min
- Decimal hours
- 8.75
- Before break
- 9 h 15 min
- Crosses midnight
- No
Decimal hours divide the minutes by 60: 8 h 45 min is 8.75 hours, not 8.45.
How to calculate the time between two times
Convert both times to minutes after midnight and subtract. 8:30 AM is 510 minutes and 5:45 PM is 1,065 minutes, so the difference is 555 minutes, or 9 hours 15 minutes. Subtract an unpaid lunch break to get the hours you are paid for.
Shifts that cross midnight
If the end time is earlier than the start time, the shift ended the next day and 24 hours are added to the end time. A shift from 10:00 PM to 6:00 AM is (6 + 24) − 22 = 8 hours. The calculator detects this automatically.
Converting to decimal hours
Timesheets and payroll often need decimal hours. Divide the minutes by 60: 7 hours 45 minutes is 7.75 hours. Writing it as 7.45 hours is a common mistake that underpays by 18 minutes.
| Minutes | Decimal |
|---|---|
| 15 | 0.25 |
| 20 | 0.33 |
| 30 | 0.50 |
| 45 | 0.75 |