Time Duration Calculator

Find the hours and minutes between two times or two dates, subtract a break, or add and subtract time from a clock time. Results in hours and minutes, decimal hours, and total minutes.

Find the hours and minutes from a start time to an end time. An end time earlier than the start counts as the next day.

Start time

End time

Unpaid break (minutes)

Include seconds

Duration

8 hours 30 minutes

9:00 AM to 5:30 PM

Decimal hours

8.50

Total minutes

510

Adding up shift durations by hand? HiveDesk records start and end times automatically and totals them on each timesheet.

Track it automatically →

Quick Answer

To find the time between two times, convert both to 24-hour format and subtract the start from the end. If the end is earlier than the start, the range crosses midnight: add 24 hours to the end time before subtracting.

Formula

Duration = End time − Start time

Add 24 hours to the end time if it is earlier than the start time

9:00 AM to 5:00 PM is 8 hours (8.00 decimal hours).
10:45 AM to 12:15 PM is 1 hour 30 minutes (90 minutes).
10:00 PM to 6:00 AM is 8 hours, crossing midnight.
8:30 AM to 5:00 PM with a 30-minute lunch is 8 hours of paid time.

How to Calculate the Time Between Two Times

There are three reliable ways to work out a duration by hand. They all give the same answer; pick the one that suits the numbers in front of you.

Method 1: Count up in steps

Count from the start time to the next whole hour, then the whole hours, then the minutes after the last whole hour. This is the easiest method for short ranges and the one most people do in their heads.

10:45 to 12:15

10:45 to 11:00 = 15 minutes
11:00 to 12:00 = 1 hour
12:00 to 12:15 = 15 minutes
Total: 1 hour 30 minutes (1.50 hours)

Method 2: Subtract in 24-hour time

Convert both times to 24-hour format (add 12 to any PM hour except 12 PM), then subtract hours from hours and minutes from minutes. When the end minutes are smaller than the start minutes, borrow one hour as 60 minutes. The military time converter has a full 24-hour chart if you need one.

9:40 AM to 5:15 PM

5:15 PM = 17:15 in 24-hour time
15 minutes is less than 40, so borrow an hour: 17:15 becomes 16:75
16:75 − 9:40 = 7 hours 35 minutes
Total: 7 hours 35 minutes (7.58 hours)

Method 3: Split at midnight

For overnight ranges, work out the time from the start to midnight and from midnight to the end, then add them together.

10:30 PM to 6:15 AM

10:30 PM to midnight = 1 hour 30 minutes
Midnight to 6:15 AM = 6 hours 15 minutes
Total: 7 hours 45 minutes (7.75 hours)

Common Time Durations

The time ranges people look up most often, worked out in hours and minutes, decimal hours, and total minutes. Ranges where the end time is earlier than the start run into the next day.

Short ranges (under two hours)

From	To	Duration	Decimal hours	Minutes
8:45 AM	9:30 AM	45 minutes	0.75	45
10:15 AM	10:45 AM	30 minutes	0.50	30
10:15 AM	11:30 AM	1 hour 15 minutes	1.25	75
10:30 AM	12:00 PM	1 hour 30 minutes	1.50	90
10:45 AM	11:15 AM	30 minutes	0.50	30
10:45 AM	11:25 AM	40 minutes	0.67	40
10:45 AM	11:30 AM	45 minutes	0.75	45
10:45 AM	12:15 PM	1 hour 30 minutes	1.50	90
10:45 AM	12:30 PM	1 hour 45 minutes	1.75	105
11:15 AM	11:45 AM	30 minutes	0.50	30
11:45 AM	12:30 PM	45 minutes	0.75	45
11:50 AM	12:20 PM	30 minutes	0.50	30
3:40 PM	4:30 PM	50 minutes	0.83	50
5:30 PM	6:30 PM	1 hour	1.00	60
6:30 PM	8:00 PM	1 hour 30 minutes	1.50	90

Daytime ranges

From	To	Duration	Decimal hours	Minutes
7:00 AM	3:30 PM	8 hours 30 minutes	8.50	510
7:15 AM	1:45 PM	6 hours 30 minutes	6.50	390
8:00 AM	5:00 PM	9 hours	9.00	540
8:30 AM	5:00 PM	8 hours 30 minutes	8.50	510
9:00 AM	5:00 PM	8 hours	8.00	480
9:00 AM	5:30 PM	8 hours 30 minutes	8.50	510
9:00 AM	6:00 PM	9 hours	9.00	540
10:00 AM	1:00 PM	3 hours	3.00	180
10:00 AM	5:00 PM	7 hours	7.00	420
10:00 AM	5:30 PM	7 hours 30 minutes	7.50	450
10:30 AM	2:00 PM	3 hours 30 minutes	3.50	210
10:30 AM	5:00 PM	6 hours 30 minutes	6.50	390
11:00 AM	5:30 PM	6 hours 30 minutes	6.50	390
11:00 AM	6:30 PM	7 hours 30 minutes	7.50	450
11:00 AM	10:00 PM	11 hours	11.00	660
11:30 AM	2:00 PM	2 hours 30 minutes	2.50	150
11:30 AM	3:00 PM	3 hours 30 minutes	3.50	210
11:30 AM	4:00 PM	4 hours 30 minutes	4.50	270
11:30 AM	5:00 PM	5 hours 30 minutes	5.50	330
11:30 AM	5:30 PM	6 hours	6.00	360
11:30 AM	6:00 PM	6 hours 30 minutes	6.50	390
12:00 PM	5:30 PM	5 hours 30 minutes	5.50	330
12:45 PM	4:45 PM	4 hours	4.00	240
2:00 PM	6:00 PM	4 hours	4.00	240
2:30 PM	5:00 PM	2 hours 30 minutes	2.50	150
6:45 AM	6:30 PM	11 hours 45 minutes	11.75	705

Overnight ranges

From	To	Duration	Decimal hours	Minutes
3:00 PM	11:00 PM	8 hours	8.00	480
7:00 PM	7:00 AM (next day)	12 hours	12.00	720
8:00 PM	6:00 AM (next day)	10 hours	10.00	600
10:00 PM	2:00 AM (next day)	4 hours	4.00	240
10:00 PM	5:00 AM (next day)	7 hours	7.00	420
10:00 PM	5:30 AM (next day)	7 hours 30 minutes	7.50	450
10:00 PM	6:00 AM (next day)	8 hours	8.00	480
10:45 PM	5:00 AM (next day)	6 hours 15 minutes	6.25	375
11:00 PM	5:00 AM (next day)	6 hours	6.00	360
11:00 PM	5:30 AM (next day)	6 hours 30 minutes	6.50	390
11:00 PM	7:00 AM (next day)	8 hours	8.00	480
11:30 PM	5:30 AM (next day)	6 hours	6.00	360
6:00 PM	1:00 PM (next day)	19 hours	19.00	1140
10:00 PM	2:00 PM (next day)	16 hours	16.00	960
11:00 PM	2:00 PM (next day)	15 hours	15.00	900

Common Shift Lengths

A shift's span (clock-in to clock-out) is not the same as its paid time when there is an unpaid meal break. Under the federal Fair Labor Standards Act, rest breaks of 5 to 20 minutes count as paid work time, while meal periods of 30 minutes or more can be unpaid if the employee is fully relieved of duty.

Shift	Typical times	Span	Unpaid meal	Paid hours
8-hour day shift	9:00 AM to 5:00 PM	8 hours	30 min	7.50
8 paid hours with lunch	8:00 AM to 4:30 PM	8 hours 30 minutes	30 min	8.00
10-hour shift (4/10 week)	7:00 AM to 5:30 PM	10 hours 30 minutes	30 min	10.00
12-hour day shift	7:00 AM to 7:00 PM	12 hours	30 min	11.50
12-hour night shift	7:00 PM to 7:00 AM	12 hours	30 min	11.50
Second shift	3:00 PM to 11:00 PM	8 hours	30 min	7.50
Third (graveyard) shift	11:00 PM to 7:00 AM	8 hours	30 min	7.50
Part-time half day	9:00 AM to 1:00 PM	4 hours	None	4.00

Many states set their own meal and rest break rules on top of federal law, and the break time calculator covers the common state requirements. For more on shift patterns, see first, second, and third shift hours and the shift schedule generator.

Converting a Duration to Decimal Hours

Payroll, invoicing, and spreadsheets need durations as decimal hours, because 7 hours 45 minutes cannot be multiplied by an hourly rate until it is written as 7.75. Divide the minutes by 60 and add them to the whole hours.

5 minutes

0.08 hr

10 minutes

0.17 hr

15 minutes

0.25 hr

20 minutes

0.33 hr

25 minutes

0.42 hr

30 minutes

0.50 hr

35 minutes

0.58 hr

40 minutes

0.67 hr

45 minutes

0.75 hr

50 minutes

0.83 hr

55 minutes

0.92 hr

60 minutes

1.00 hr

The minutes to decimal calculator has the full 1 to 60 minute chart and explains quarter-hour rounding. A common mistake is writing 7 hours 45 minutes as 7.45; that understates the time by 18 minutes, and on a timesheet it underpays the employee.

Time Duration Formulas for Excel and Google Sheets

Spreadsheets store a time as a fraction of a 24-hour day, so subtracting two times gives a fraction that needs formatting or converting. With the start time in A2 and the end time in B2:

You want	Formula	Format the cell as
Hours and minutes, same day	=B2-A2	[h]:mm
Hours and minutes, may cross midnight	=MOD(B2-A2,1)	[h]:mm
Decimal hours	=MOD(B2-A2,1)*24	Number, 2 decimals
Total minutes	=MOD(B2-A2,1)*1440	Number
Decimal hours minus a 30-minute break	=MOD(B2-A2,1)*24-0.5	Number, 2 decimals
Hours between two date-times	=(B2-A2)*24	Number, 2 decimals

The square brackets in [h]:mm matter: plain h:mm resets to zero every 24 hours, so a 26-hour total displays as 2:00. MOD(…,1) is what makes overnight ranges work; without it, 10 PM to 6 AM returns a negative time, which Excel shows as a row of # signs.

Daylight Saving Time, Rounding, and Payroll

Clock times and elapsed time are not always the same. In most of the United States, clocks move forward at 2 AM on the second Sunday in March and back at 2 AM on the first Sunday in November (March 8 and November 1 in 2026). A 10 PM to 6 AM shift on those nights lasts 7 hours in March and 9 hours in November. Non-exempt employees must be paid for the hours they actually work, so the extra hour in November is paid time. The Between Dates tab above uses your device's time zone and reflects the change.

Rounding is the other place durations go wrong. Federal rules (29 CFR 785.48) allow employers to round clock times to the nearest 5 minutes, tenth of an hour, or quarter hour, but only if the rounding averages out so employees are paid for all the time they actually work. Rounding that always favors the employer is not allowed.

For a week of shifts, the time card calculator totals each day and applies overtime, and the hours calculator adds up multiple durations. In a contact center, where agents log in and out of queues many times a day, automatic agent time tracking removes the manual arithmetic entirely.

Stop Calculating Shift Hours by Hand

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Frequently Asked Questions

How do I calculate the time between two times?

Convert both times to 24-hour format and subtract the start from the end. If the end minutes are smaller than the start minutes, borrow an hour: 17:15 minus 9:40 becomes 16:75 minus 9:40, which is 7 hours 35 minutes. If the end time is earlier than the start time, the range crosses midnight, so add 24 hours to the end time first.

How many hours is 9 AM to 5 PM?

9 AM to 5 PM is 8 hours (8.00 decimal hours). With a 30-minute unpaid lunch, it is 7 hours 30 minutes of paid time (7.50 hours).

How do I calculate the hours for an overnight shift?

Count the time up to midnight, then add the time after midnight. For 10:30 PM to 6:15 AM, that is 1 hour 30 minutes before midnight plus 6 hours 15 minutes after, for 7 hours 45 minutes (7.75 hours). The calculator does this automatically whenever the end time is earlier than the start time.

How do I convert hours and minutes to decimal hours?

Divide the minutes by 60 and add the result to the hours. 7 hours 45 minutes is 7 + 45/60 = 7.75 hours; 20 minutes is 0.33 hours. Payroll and billing systems use decimal hours because they can be multiplied by an hourly rate directly.

How do I calculate time duration in Excel or Google Sheets?

Put the start time in A2 and the end time in B2, then use =MOD(B2-A2,1) and format the cell as [h]:mm. MOD handles ranges that cross midnight. For decimal hours use =MOD(B2-A2,1)*24, and for minutes use =MOD(B2-A2,1)*1440. If the cells hold full dates and times, use =(B2-A2)*24 instead.

Does daylight saving time change the duration?

Yes, for ranges that span the change. In the United States clocks spring forward at 2 AM on the second Sunday in March and fall back at 2 AM on the first Sunday in November, so an overnight shift on those nights is one hour shorter or longer than the clock times suggest. The Between Dates tab uses your device's time zone and accounts for this; the Between Two Times tab does not.

How do I add hours to a time?

Add the hours to the hour part and the minutes to the minute part, carrying 60 minutes into an hour and wrapping past 24:00 into the next day. 9:00 AM plus 8 hours 30 minutes is 5:30 PM; 10:00 PM plus 9 hours is 7:00 AM the next day. The Add or Subtract tab does this for you.

How many minutes are in 1.5 hours?

90 minutes. Multiply decimal hours by 60 to get minutes: 1.5 × 60 = 90, 0.75 × 60 = 45, and 2.25 × 60 = 135.