How many hours between times?
Enter a start time and an end time. The hours between them show as hours and minutes and as decimal hours.
- Hours
- 8.5
From 9:00 AM to 5:30 PM is 8.5 hours (510 minutes).
- Hours and minutes
- 8 hours, 30 minutes
- Minutes
- 510
- Ends the next day
- No
Hours: 8.5. From 9:00 AM to 5:30 PM is 8.5 hours (510 minutes).
How to calculate
Counts the hours and minutes between two clock times, as decimal hours for timesheets, with an end time before the start counted on the next day.
Example with the default inputs (Start time 09:00, End time 17:30): From 9:00 AM to 5:30 PM is 8.5 hours (510 minutes).
Method: minutes = end − start in minutes, plus 24 × 60 when the end is earlier than the start; hours = minutes ÷ 60.
- Times are on a 24-hour clock with no date. An end time earlier than the start time is on the next day, so the answer is always under 24 hours.
- The same start and end time gives 0 hours.
- Clock changes for daylight saving time are not counted: every hour is 60 minutes.
Worked examples
Each example is checked against the calculator on every build.
- Start time 09:00, End time 17:30 gives Hours 8.5, Hours and minutes 8 hours, 30 minutes, Minutes 510, Ends the next day no.Source: hand calculation in content.mdx: 17:30 − 9:00 = 8 h 30 min = 510 ÷ 60 = 8.5 hours
- Start time 22:00, End time 06:15 gives Hours 8.25, Hours and minutes 8 hours, 15 minutes, Minutes 495, Ends the next day yes.Source: hand calculation in content.mdx: 6:15 + 24:00 − 22:00 = 8 h 15 min
- Start time 08:40, End time 12:05 gives Hours 3.416667, Hours and minutes 3 hours, 25 minutes, Minutes 205.Source: hand calculation in content.mdx: 12:05 − 8:40 = 3 h 25 min = 205 ÷ 60 = 3.4167 hours
- Start time 13:45, End time 13:45 gives Hours 0, Minutes 0, Ends the next day no.Source: hand calculation in content.mdx: the same time is 0 hours
How it works
Both times are on a 24-hour clock (a time such as 5:30 PM is 17:30). The calculator turns each into minutes after midnight, hours × 60 + minutes, and subtracts:
minutes = end − start
If the end time is earlier than the start time, the period runs past midnight, so 24 × 60 = 1,440 minutes are added:
minutes = end − start + 1,440
Then:
- hours and minutes = the whole hours in the minutes (minutes ÷ 60, rounded down) and the minutes left over
- decimal hours = minutes ÷ 60
Assumptions
- A 0-minute answer shows as 0 hours, with no hours-and-minutes line. A seconds part of a time is dropped (09:00:30 counts as 09:00).
- The answer is from 0 up to (but not including) 24 hours. The same start and end time gives 0.
- There are no dates, time zones, or daylight saving changes: every hour is 60 minutes.
- Times are whole minutes. Decimal hours show two decimal places; the full value is kept.
Worked examples by hand
9:00 AM to 5:30 PM. 17:30 is 1,050 minutes and 9:00 is 540 minutes. 1,050 − 540 = 510 minutes, which is 8 hours 30 minutes, or 510 ÷ 60 = 8.5 hours.
10:00 PM to 6:15 AM. 6:15 is 375 minutes and 22:00 is 1,320 minutes. The end is earlier, so add a day: 375 + 1,440 − 1,320 = 495 minutes = 8 hours 15 minutes = 8.25 hours, ending the next day.
8:40 AM to 12:05 PM. 725 − 520 = 205 minutes = 3 hours 25 minutes = 205 ÷ 60 = 3.42 hours (3.4167).
1:45 PM to 1:45 PM. The same time: 0 hours.
Other questions people ask
How do I calculate the hours between two times?
Subtract the start time from the end time. From 9:00 AM to 5:30 PM is 17:30 − 9:00 = 8 hours 30 minutes. To get decimal hours, divide the minutes by 60: 30 ÷ 60 = 0.5, so 8.5 hours.
How do I count hours past midnight?
Add 24 hours to the end time when it is earlier than the start. From 10:00 PM to 6:15 AM is 6:15 + 24:00 − 22:00 = 8 hours 15 minutes, or 8.25 hours. The calculator does this for you.
How do I turn minutes into decimal hours?
Divide the minutes by 60. 15 minutes is 0.25 hours, 20 minutes is 0.33, 30 minutes is 0.5, and 45 minutes is 0.75. So 3 hours 25 minutes is 3 + 25 ÷ 60 = 3.42 hours.
What about a span longer than 24 hours?
Times without dates cannot show more than 24 hours. Use the time duration calculator, which takes a date with each time.
Does daylight saving time change the answer?
No. The calculator counts clock time: every hour is 60 minutes and there is no time zone. A night shift during the spring or fall clock change is really one hour shorter or longer than the clock times show.
What if the start and end times are the same?
The answer is 0 hours. For a full 24-hour shift, use the time duration calculator with the two dates.