Calculators & everyday math
How to Calculate Hours Between Two Times
Working out the time between two clock times — a shift, a class, a same-day trip — is a subtraction in base 60. This guide shows how to do it by hand, how to handle 12-hour times, and how to check a timesheet.
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Subtract hours and minutes
- Write both times in 24-hour form: 9:15 AM is 09:15 and 5:40 PM is 17:40.
- Subtract the minutes: 40 − 15 = 25.
- Subtract the hours: 17 − 9 = 8.
- The span is 8 hours 25 minutes.
When you need to borrow
If the end minutes are smaller than the start minutes, borrow an hour as 60 minutes. From 8:50 AM to 3:20 PM, 15:20 becomes 14:80, and 14:80 − 8:50 = 6 hours 30 minutes.
12-hour and 24-hour times
| 12-hour | 24-hour |
|---|---|
| 12:00 AM (midnight) | 00:00 |
| 1:00 AM | 01:00 |
| 12:00 PM (noon) | 12:00 |
| 1:00 PM | 13:00 |
| 11:59 PM | 23:59 |
Checking a timesheet
- Work out each day’s span separately, then add the spans with the Time Duration Calculator.
- Subtract unpaid breaks from the span, not from the start or end time.
- Keep hours and minutes separate until the end, or convert everything to decimal hours consistently.
Hours Between Times FAQ
- How do I calculate hours worked from a start and end time?
- Subtract the start time from the end time: 9:00 AM to 5:30 PM is 8 hours 30 minutes. Subtract any unpaid break afterward.
- How do I subtract times when the end minutes are smaller?
- Borrow 60 minutes from the hours before subtracting.
- Is 12:00 PM noon or midnight?
- Noon. 12:00 AM is midnight.
- What if the times cross midnight?
- Add 24 hours to the end time before subtracting, as the guide on overnight spans explains.
- How many hours is 9 to 5?
- 8 hours.
Related guides
- Overnight Time SpansMeasure a span that crosses midnight, such as a night shift, why adding 24 hours works, and what changes on the nights the clocks move.
- Decimal HoursConvert between hours and minutes and decimal hours for timesheets, with a quick conversion table and the mistakes that change a total.
Open the tool
Jump into Hours Between Times Calculator when you are ready to process your files.
