Time Duration Calculator

Find the duration between two clock times, including overnight spans that cross midnight.

  • Free to use
  • Accurate results
  • No registration required
  • Works on all devices
Enter a start time and end time to find the duration between them, in hours and minutes.
Use 24-hour HH:MM format, e.g. 09:00 or 17:45.

Your result

8

Hours

Minutes30
Total hours (decimal)8.5
Crosses midnight?No

AI explanation

Formula

Duration = end time − start time; if end time is earlier than start time, it's assumed to fall on the next day

Worked example

9:00 to 17:30

Worked example: 9:00 to 17:30
FieldValue
Start time (24-hour)09:00
End time (24-hour)17:30
Hours8
Minutes30
Total hours (decimal)8.5
Crosses midnight?No

Assumptions

  • If the end time is earlier than the start time, the duration is calculated assuming the end time falls on the following day (e.g. a night shift from 22:00 to 06:00).

Frequently asked questions

How does this handle an overnight duration?

If the end time is earlier than the start time (e.g. 22:00 to 06:00), the calculator assumes the end time is on the following day and computes the duration accordingly.

Can I get the result as decimal hours instead of hours and minutes?

Yes — the "Total hours (decimal)" output gives the duration as a single decimal number, useful for timesheets and payroll.

Is there a version of this for full work shifts with a lunch break?

Yes — see the Time Card Calculator, which also subtracts unpaid break time.

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