Find the exact duration between a start time and an end time, even if the end time crosses into the next day.
Time Duration Calculator
LiveDuration
8h 30m
In decimal hours
8.5
The formula
Duration = End time - Start time (add 24 hours if the end time crosses midnight)
Example
9:15 AM to 5:45 PM: duration = 8h 30m, or 8.5 hours in decimal.
Step-by-step guide
- Enter the start time and end time.
- Select "Crosses midnight" if the end time is on the following day (like an overnight shift).
- Read the duration in hours and minutes, plus decimal hours.
Common mistakes
Forgetting to mark an overnight shift - without it, an end time earlier than the start time (like 11 PM to 7 AM) would show as invalid or negative.
Mixing up decimal hours with hours-and-minutes when entering timesheets - 8.5 hours is 8 hours 30 minutes, not 8 hours 50 minutes.
Frequently asked questions
What's the difference between decimal hours and hours/minutes?
Decimal hours express minutes as a fraction of an hour (30 minutes = 0.5), which is the format many payroll and billing systems expect instead of hours and minutes separately.
How do I handle an overnight shift?
Select "Crosses midnight" - this adds 24 hours before subtracting, correctly handling a start time later in the day than the end time.
Does this subtract unpaid breaks automatically?
No - this shows the raw time span. For tracking a full workday with breaks, our Time Card Calculator handles multiple time segments.
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