Work out how many hours you worked from a start time, an end time and an unpaid break. Overnight shifts are handled too — an end time earlier than the start counts as the next morning.
Hours Calculator
How the Hours Calculator Works
The Hours Calculator works out how long a period between two clock times lasts, such as a work shift, a study session, a hire period, or a journey, and it adjusts for an unpaid break. You enter a start time and an end time, add any break minutes to remove, and it returns the length of the period in hours and minutes and in decimal hours. Employees checking timesheets, managers preparing rotas, and freelancers logging billable time will find it quicker and more reliable than counting around a clock face by hand.
The method starts by converting both clock times into minutes since midnight, so a time like 17:30 becomes 1,050 minutes. The start minutes are subtracted from the end minutes to get the raw length of the period. If the end time is earlier than the start time, the calculator adds 24 hours, which is 1,440 minutes, before subtracting, because the period must have run past midnight. It then subtracts the unpaid break minutes you entered, and the result is never allowed to fall below zero. Finally it presents the remaining minutes as hours and minutes and as decimal hours, found by dividing by 60.
This calculator implements that logic for both ordinary daytime periods and overnight shifts, with no separate setting to switch on. A shift from 22:00 to 06:00, for example, is correctly treated as running through midnight rather than as a negative length. Break time is entered in minutes, so a half-hour lunch is 30, and it is removed only once, from the whole period. If the break is longer than the period itself, the result stops at zero, a clear signal to recheck your entries.
How to Use This Calculator
- Enter the time the period started in the start time field, using the clock format shown.
- Enter the time the period ended in the end time field, even if that time is after midnight.
- Type any unpaid break in minutes, or leave it at zero if there was no break to remove.
- Press Calculate to work out the length of the period.
- Read the result in hours and minutes, and note the decimal hours and total minutes for a timesheet or invoice.
Example
For a tested example, enter a start time of 09:00 and an end time of 17:30, with a 30-minute break. The raw period from 09:00 to 17:30 is eight hours and thirty minutes, or 510 minutes. Subtracting the 30-minute unpaid break leaves 480 minutes. The final result is therefore 480 minutes = 8.00 hours, shown as 8 hours and 0 minutes and as 8.00 decimal hours, ready for a timesheet or a pay calculation.
As a second example, take an overnight shift with a start time of 22:00 and an end time of 06:00, with no break. Because the end time is earlier than the start time, the calculator adds 24 hours and treats the shift as running past midnight. The result is 8.00 hours, with no negative figure and no manual adjustment needed.
Understanding Your Result
Decimal hours are the figure most payroll systems and invoices use, because they can be multiplied directly by an hourly rate. An answer of 8.00 hours at a given rate is simply eight times that rate, while 7.50 hours means seven hours and thirty minutes, not seven hours and fifty minutes. The hours and minutes form is easier to compare with your rota, and total minutes are handy for records that log time in a single unit.
For the most reliable results, use these habits:
- Enter times exactly as they appear on your rota or clock record, and double-check morning and evening times if a 12-hour clock is used anywhere.
- Only subtract breaks that are genuinely unpaid and were actually taken, because an assumed break will understate your hours.
- For overnight work, do not split the shift at midnight unless your employer records it that way; enter the real start and finish as one period.
Hours Calculator FAQs
How does the calculator handle an overnight shift?
If the end time is earlier than the start time, it adds 24 hours before subtracting, assuming the period ran past midnight. So a shift from 22:00 to 06:00 is correctly worked out as eight hours, not a negative number.
Why should I enter break time in minutes?
Breaks are entered in minutes so they can be recorded exactly, such as 15, 30, or 45 minutes. They are subtracted once, and only the remaining paid time is shown.
What does decimal hours mean on a timesheet?
Decimal hours express your worked time as a fraction of an hour, so 8.50 hours is eight hours and thirty minutes of work. Payroll and invoicing use this form because the figure can be multiplied straight by an hourly rate to calculate pay.
What if I enter a break longer than my shift?
The result will never go below zero, so the calculator will show zero rather than negative hours. That outcome usually means a time or the break length was typed incorrectly, so check all three entries and calculate again.
Can I use this for things other than work shifts?
Yes, any period between two clock times works, including study sessions, equipment hire, travel, and childcare hours. Enter the start and finish, add any pause as a break, and read the length.
Related calculators: Time Calculator, Salary Calculator, Date Calculator.