Example 1
- Mode: time between hours
- Start 08:00, end 16:30
8 hours 30 minutes
How many hours from 8:00 to 16:30? 8 hours and 30 minutes, which is 8.5 h.
Hours Calculator
The calculator counts minutes between two clock times. From 8:00 to 16:30 is 8 hours and 30 minutes, which is 8.5 hours. When the end is earlier than the start, the result crosses midnight.
This is not a time card and not overtime pay. Overtime rates are on the overtime calculator. Civil days between dates are on the date difference page.
Result
Enter the clock times. The span or the new clock time appears here.
How it works
The calculator turns a clock time into minutes after midnight and subtracts the start from the end. 8:00 is 480 minutes, 16:30 is 990 minutes, and the difference is 510 minutes, which is 8 hours and 30 minutes. The same 510 divided by 60 is 8.5 h.
When the end is earlier than the start, the calculator adds 1440 minutes, one clock day, to the end. 22:00 is 1320 minutes, 6:00 is 360 minutes, 360 plus 1440 is 1800, and 1800 minus 1320 is 480 minutes, which is 8 hours.
The calculator subtracts an optional break from that span. From 8:00 to 16:30 with a 30-minute break, 8 hours remain. An empty break field does not change the span.
In add and subtract mode the calculator moves the start time by the hours and minutes you enter. 14:45 plus 2 hours and 30 minutes is 17:15. If the result crosses midnight, the clock wraps and the note says how many days it moved.
The same clock times in span mode give 0 minutes, not a full day. Add 24 hours in add mode for a full day. The calculator has no date and no time zone, so a daylight-saving change does not shorten the night.
This is not a time card and not overtime. Civil days between two dates are on the date-difference page. A string such as 1h 30min 45s belongs on the duration-parsing page.
Formula
minutes = end − start; if end < start, end = end + 1440
Decimal hours = minutes / 60. After adding: new time = (start + hours × 60 + minutes) modulo 1440.
How to use it
- Choose time between hours, add, or subtract.
- For a span, enter a start and an end, for example 8:00 and 16:30. The result is 8 hours and 30 minutes.
- When the end is earlier, for example 22:00 and 6:00, the result crosses midnight and is 8 hours.
- Leave the break empty or enter 30. From 8:00 to 16:30 with 30 break minutes, 8 hours remain.
- In add mode enter a start plus hours and minutes. 14:45 plus 2 and 30 is 17:15.
8 h 30 min from 8:00 to 16:30
The calculator subtracts start minutes from end minutes. 8:00 to 16:30 is 510 minutes, which is 8 hours and 30 minutes.
- min
- Minutes after midnight. 8:00 is 480. 16:30 is 990. The 510 difference is 8 hours and 30 minutes.
- 8.5 h
- Decimal hours: 510 / 60. That is a spreadsheet form, not a different span.
- 1440
- Minutes in a full day. They are added when the end is earlier than the start, for example 22:00 to 6:00.
Examples
Example 2
- Mode: time between hours
- Start 22:00, end 06:00
8 hours
From 22:00 to 6:00 the result crosses midnight and is 8 hours, which is 480 minutes.
Example 3
- Mode: add hours and minutes
- Start 14:45, plus 2 h and 30 min
17:15
14:45 plus 2 hours and 30 minutes is 17:15 on the same clock day.
Related calculators
Frequently asked questions
How many hours are there from 8:00 to 16:30?
8 hours and 30 minutes, which is 8.5 h and 510 minutes. The calculator subtracts the start minutes from the end minutes.
How many hours are there from 22:00 to 6:00?
8 hours. The end is earlier than the start, so the result crosses midnight. That is 480 minutes, not a daylight-saving change.
What is 14:45 plus 2 hours and 30 minutes?
17:15 on the same clock day. 14:45 is 885 minutes after midnight; plus 150 minutes is 1035, which is 17:15.
Is this an overtime or time-card calculator?
No. Here you count clock hours. Pay rates and overtime are on a separate salary page.
Does a 30-minute break shorten 8:00-16:30?
Yes. 8 hours 30 minutes minus a 30-minute break is 8 hours. An empty break field does not change the span.
What if both times are the same?
The result is 0 minutes, not a full day. Add 24 hours in the add mode for a full day.
Does a DST change shorten the night from 2:00 to 3:00?
No. The calculator counts clock minutes without a date and without a time zone. 22:00 to 6:00 is always 8 hours.
How is this different from the date difference?
The date page counts civil days, for example 366 days in a leap year. Here you count hours and minutes on one or two clock days.
Is 2.5 hours the same as 2 hours 30 minutes?
Yes, in add mode. 2.5 times 60 is 150 minutes, the same as 2 hours and 30 minutes.
Where do I paste 1h 30min 45s?
On the duration-parsing page in the IT calculators. Here you enter hours in the fields, not in that string.
Sources
A clock hour has 60 minutes. A full day has 1440 minutes.
Page updated in 2026.