Hours Between Times Calculator
Calculate hours between times with calendar-date arithmetic.
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What this tool does
Calculate hours between times with calendar-date arithmetic. An earlier end time means overnight; equal times mean zero duration, not 24 hours.
How to use the Hours Between Times Calculator
- Enter or select start time (hh:mm).
- Enter or select end time (hh:mm).
- Read the calculated result; change any measurement to compare alternatives.
Formula
elapsed minutes=(end−start+1440)%1440; hours=minutes/60
- start
- Start time (HH:MM)
- end
- End time (HH:MM)
An earlier end time means overnight; equal times mean zero duration, not 24 hours.
Worked example
For hours between times calculator, the following measurements illustrate the exact method: Start time (HH:MM): 09:00; End time (HH:MM): 17:30.
Inputs
- Start time (HH:MM)09:00
- End time (HH:MM)17:30
Result
- Duration (hours)8.5
- Hours and minutes8h 30m
Results explained
- Duration (hours)
- Duration (hours) from the formula above. An earlier end time means overnight; equal times mean zero duration, not 24 hours.
- Hours and minutes
- Hours and minutes from the formula above. An earlier end time means overnight; equal times mean zero duration, not 24 hours.
Frequently asked questions
elapsed minutes=(end−start+1440)%1440; hours=minutes/60
An earlier end time means overnight; equal times mean zero duration, not 24 hours.
Yes. Valid calendar dates use Gregorian leap-year rules.
Date-only calculations use UTC calendar days to avoid daylight-saving shifts. Clock-time durations use the provided elapsed clock times, not a timezone database.
Check the date format, direction, whether endpoints are included, and whether holidays need to be excluded.