Time Duration Calculator
Find the exact hours, minutes and seconds between two clock times. Overnight times are handled automatically.
Duration
8h 00m
Decimal hours
8.00
Total minutes
480
Total seconds
28,800
Calculating a work shift with an unpaid break? Use our Time Card Calculator.
How to Use the Time Duration Calculator
Choose 12-hour or 24-hour display, then enter a start time and an end time. The result updates automatically. Turn on Include seconds if you need precision down to the second.
How Time Duration Is Calculated
The calculator converts each clock time into seconds since midnight. It subtracts the start from the end. If the end time is earlier, it adds 24 hours (86,400 seconds) to the end time so the result spans overnight correctly.
Calculating Time Across Midnight
Example: 10:00 PM to 6:00 AM is calculated as 8 hours because 6:00 AM is treated as the next day. No extra checkbox is needed.
Time Duration Examples
- 09:00 → 17:00 = 8h 00m
- 09:15 → 17:45 = 8h 30m
- 22:00 → 06:00 = 8h 00m
- 09:00:30 → 09:01:45 = 1m 15s
Time Duration and Decimal Hours
Decimal hours make payroll and billing easier. For example, 8 hours and 30 minutes equals 8.50 decimal hours. Need to convert another hours-and-minutes value? Use our Decimal Hours Calculator.