Time Duration Calculator
Count the hours. Make every minute count.
Calculate the hours and minutes between two times, subtract unpaid breaks, or add multiple work shifts together. Get results in hours, minutes and decimal hours.
🕒 Calculate your time
🌙 If the end time is earlier than the start time, the calculator automatically treats it as the following day. Identical times represent zero duration.
⚙️ Calculation assumptions
Times are calculated using a 24-hour clock internally, regardless of your browser’s time display. All calculations are based on clock times, not specific dates.
A single shift can last up to 24 hours. Daylight saving changes, time zones, overtime rules and paid-break policies are not automatically applied.
Decimal hours are useful for timesheets. For example, 7 hours and 30 minutes equals 7.5 hours, not 7.30 hours.
🧠 How to calculate time duration
To find the duration between two times, convert both clock times into minutes after midnight, then subtract the starting time from the ending time. For an overnight shift, add 24 hours when the ending time is earlier.
Divide the net minutes by 60 to convert the result into decimal hours.
🧮 Example: A regular work shift
Suppose you work from 9:00 AM to 5:30 PM and take a 30-minute unpaid lunch.
The total elapsed time is 8 hours and 30 minutes. After subtracting lunch, you’ve worked eight hours.
🌙 Calculating overnight shifts
If you start work at 10:00 PM and finish at 6:00 AM the next day, your gross shift duration is eight hours. A 30-minute unpaid break would reduce your net working time to seven hours and 30 minutes.
💡 Frequently Asked Questions
Enter the start and end times. The calculator determines elapsed hours and minutes automatically, including overnight periods.
Yes. If your end time is earlier than your start time, the calculator assumes the shift ends the following day.
Divide the minutes by 60 and add the result to the whole hours. For example, 7 hours and 45 minutes equals 7.75 decimal hours.
Yes. Enter the unpaid break in minutes. The calculator subtracts it from the gross duration to calculate net working time.
Yes. Switch to Add Work Shifts and enter each shift separately. The calculator totals the gross time, unpaid breaks and net hours.
No. It calculates clock-time differences without specific dates or time zones. A shift crossing a daylight saving change may have a different actual elapsed duration.