Time Duration Calculator
Calculate elapsed time between two clock times, including overnight shifts.
Enter your values
Use the fields below, then select Calculate. Your result appears immediately on this page.
How to use the Time Duration Calculator
Enter a start and end clock time. Enable the overnight option when an end time earlier than the start should be treated as the next day.
Formula / calculation logic
Duration = End time − Start time, with 24 hours added when the overnight rule is enabled and needed.
Worked example
22:00 to 06:00 with overnight enabled is an 8-hour duration.
Important notes
This tool measures elapsed clock time and does not apply payroll rounding, scheduled breaks or daylight-saving transitions across dated shifts.
Frequently asked questions
What happens if end time is earlier than start time?
Enable the overnight option to treat the end as the next day.
Does it subtract breaks?
Use the Working Hours Calculator when you need break subtraction.