Time & Hours Calculator
Enter two clock times to find the elapsed hours and minutes between them, including overnight periods. You can also subtract a break to calculate worked hours or add and subtract hours and minutes from a starting time.
Time between
8 hr 30 min
Elapsed time between the two clock times.
- Total minutes
- 510
- Decimal hours
- 8.50
- Ends
- Same day
How to Use the Time Calculator
Choose Time between to calculate the duration from one clock time to another. Enter the start and end times and the result shows hours, minutes, total minutes, and decimal hours.
Choose Work hours to subtract an unpaid break from the full time between the start and end of a shift.
Choose Add / subtract when you want to move a clock time forward or backward by a number of hours and minutes.
How to Calculate Time Between Two Times
Elapsed time is the difference between the start and end clock times. For example, 09:00 to 17:30 is 8 hours 30 minutes.
The calculator also converts the duration into total minutes and decimal hours. Eight hours 30 minutes is 510 minutes, or 8.50 decimal hours.
If the end time is earlier than the start time, the calculator assumes the period crosses midnight into the following day.
Overnight Time Calculations
An overnight interval crosses midnight. For example, 22:30 to 06:30 is treated as 22:30 today to 06:30 the following day.
That interval is 8 hours, even though 06:30 is numerically earlier on a 24-hour clock.
If the start and end times are identical, this calculator reports zero elapsed time rather than assuming a full 24-hour period.
How to Calculate Work Hours
Work Hours mode first finds the gross time between the shift start and end, then subtracts the break duration.
For example, a shift from 09:00 to 17:30 lasts 8 hours 30 minutes. Subtracting a 30-minute break leaves 8 hours of worked time.
Breaks are entered in whole minutes and cannot be longer than the full shift.
Gross Hours vs Worked Hours
Gross time is the full duration from the start of a shift to the end. Worked time is the gross duration after subtracting the entered break.
For a 9-hour shift with a 1-hour unpaid break, the gross time is 9 hours while the worked time is 8 hours.
The calculator does not make assumptions about paid or unpaid breaks. It simply subtracts the break duration you enter.
Decimal Hours
Decimal hours express minutes as a fraction of an hour. Divide the number of minutes by 60 to convert them.
For example, 30 minutes is 0.50 hour, 15 minutes is 0.25 hour, and 45 minutes is 0.75 hour.
A duration of 7 hours 30 minutes therefore equals 7.50 decimal hours.
Adding Hours and Minutes to a Time
Add / subtract mode starts with one clock time and moves it forward or backward by the amount you enter.
For example, adding 2 hours 45 minutes to 21:30 gives 00:15 on the following day.
The result includes a day offset when the adjustment crosses midnight.
Subtracting Time From a Clock Time
Subtracting time works in the opposite direction. For example, subtracting 3 hours from 01:30 gives 22:30 on the previous day.
Large adjustments can cross more than one calendar day. The calculator reports how many days earlier or later the resulting clock time falls.
24-Hour Time
The calculator uses 24-hour clock input so each time has only one interpretation. For example, 09:00 is 9:00 AM and 21:00 is 9:00 PM.
Midnight is written as 00:00 and noon as 12:00.
Using 24-hour time avoids ambiguity between morning and evening times.
Time and Hours Formulas
Clock times can be converted to minutes after midnight, making elapsed-time and work-hour calculations straightforward.
- Hour on a 24-hour clock
- Minutes within the hour
- Total minutes
- Elapsed minutes
- Minutes in 24 hours
Examples
Time between two times
09:00 to 17:30
8 hr 30 min, or 8.50 decimal hours.
Overnight duration
22:30 to 06:30
8 hr; the end time is on the next day.
Work hours with a break
09:00 to 17:30 with a 30-minute break
8 hr worked.
Add time
21:30 + 2 hr 45 min
00:15, one day later.
Subtract time
01:30 − 3 hr
22:30, one day earlier.
Same start and end time
12:00 to 12:00
0 hr elapsed.
Frequently Asked Questions
How do I calculate hours between two times?
Enter the start and end times in Time between mode. The calculator shows the elapsed hours, minutes, total minutes, and decimal hours.
How are overnight hours calculated?
If the end time is earlier than the start time, the calculator treats the end as occurring on the following day.
What happens if the start and end times are the same?
The calculator returns zero elapsed time. It does not automatically assume a 24-hour duration.
How do I calculate work hours after a break?
Choose Work hours, enter the shift start and end times, then enter the break duration in minutes. The break is subtracted from the gross shift time.
What is the difference between gross hours and worked hours?
Gross hours are the full time between the start and end of the shift. Worked hours are the gross duration after subtracting the break entered.
How do I convert minutes to decimal hours?
Divide the minutes by 60. For example, 30 minutes is 0.50 hour and 45 minutes is 0.75 hour.
How many decimal hours is 8 hours 30 minutes?
8 hours 30 minutes equals 8.50 decimal hours because 30 ÷ 60 = 0.5.
Can I add hours to a time?
Yes. Use Add / subtract mode, choose Add, enter a starting time, and enter the hours and minutes you want to add.
Can I subtract hours from a time?
Yes. Choose Subtract and enter the starting clock time and amount to subtract.
What happens when adding time crosses midnight?
The clock time wraps into the next day and the calculator reports the day offset.
Does this calculator use AM and PM?
The time inputs use a 24-hour clock. For example, 09:00 is 9:00 AM and 21:00 is 9:00 PM.
Can a break be longer than the shift?
No. The break duration cannot exceed the gross time between the start and end of the shift.
Are my work hours or times uploaded anywhere?
No. All calculations run locally in your browser.