Time Duration Calculator
Enter a start and end time to calculate the duration between them, in hours and minutes.
Last updated: September 5, 2026
Frequently asked questions
How many hours between 9:00 AM and 5:30 PM?
8 hours and 30 minutes - a common full work day with a half-hour beyond the standard 8-hour shift.
What happens if the end time is earlier than the start time?
The calculator assumes the span crosses midnight into the next day - for example, 10 PM to 6 AM is treated as an 8-hour overnight duration, not a negative number.
How do I calculate duration across a time zone change?
This calculator assumes both times are in the same time zone; if you're comparing times across zones, convert both to the same time zone first (e.g., using a time zone converter), then calculate the duration between the converted times.
Can I calculate duration in decimal hours instead of hours and minutes?
Yes - alongside the hours-and-minutes breakdown, this calculator shows the total duration as a decimal (e.g., 7 hours 30 minutes displays as 7.5 hours), which is useful for timesheets and billing that require decimal time entries.
How do I calculate duration for a night shift, like 11 PM to 7 AM?
Enter 23:00 as the start and 07:00 as the end - since the end hour is numerically smaller, the calculator treats it as crossing midnight and returns 8 hours, the correct overnight shift length.
What if the start and end time are identical?
The calculator treats an identical start and end time as a full 24-hour span (crossing midnight back to the same clock time) rather than zero, since it always measures forward from start to end.
Is this the same as an 'elapsed time calculator'?
Yes - both terms describe finding the span between two clock times. This tool works specifically with hours and minutes on a 24-hour clock rather than full calendar dates.