Time Duration Calculator

Hours and minutes between a start time and an end time — decimal hours included.

FREE TOOL · WORKS OFFLINE · NO SIGN-UP

An end time earlier than the start is treated as the next day — overnight shifts and red-eye flights work automatically.

Duration
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Total minutes
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Decimal hours
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⏱️ How to Use This Time Duration Calculator

  1. 1.Enter the start time. Use the time picker or type it — both 12-hour and 24-hour entry work, depending on your device settings.
  2. 2.Enter the end time. The duration updates instantly: hours and minutes, total minutes, and decimal hours side by side.
  3. 3.Overnight spans are automatic. If the end time is earlier than the start — a night shift ending at 6 AM, a flight landing after midnight — the end is counted as the next day.
  4. 4.Use decimal hours for timesheets. Payroll systems want 8.5, not 8:30. The decimal figure shown here is the exact one to copy onto a timesheet or invoice.
  5. 5.Same time twice means zero. If start and end are identical, the duration is 0 — a full 24-hour span cannot be told apart from no time at all with only two clock times.

❓ FAQ

How do I calculate the hours between two times?

Subtract the start time from the end time. From 9:15 AM to 5:45 PM: the minutes part is 45 − 15 = 30 minutes, and the hours part is 17 − 9 = 8 hours, giving 8 hours 30 minutes. Doing it in minutes avoids borrowing mistakes: 17:45 is 1,065 minutes after midnight and 9:15 is 555, and 1,065 − 555 = 510 minutes = 8.5 hours.

What if the end time is after midnight?

When the end time is earlier than the start time, this calculator treats the end as the next day and adds 24 hours. A shift from 10:00 PM to 6:00 AM therefore comes out as 8 hours, which is exactly how overnight work, travel and sleep durations are normally counted.

How do I convert minutes to decimal hours?

Divide the minutes by 60. Thirty minutes is 30 ÷ 60 = 0.5 hours, 15 minutes is 0.25 hours, and 510 minutes is 8.5 hours. Decimal hours are what most payroll and billing systems use, so this calculator always shows both the hours-and-minutes form and the decimal form.

Is this time duration calculator free?

Yes — 100% free, no sign-up. Your times stay in your browser; nothing is uploaded, saved or tracked.

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