How work hours are calculated
Your hours worked are the time between your start and end time, minus your unpaid break. For example 09:00 to 17:30 is 8.5 hours; subtract a 30-minute break and you get 8.00 paid hours. This calculator assumes start and end fall on the same day.
Another example: a shift from 08:15 to 16:45 is 8 hours 30 minutes of elapsed time, and a 45-minute unpaid break leaves 7.75 hours worked. Do the subtraction in minutes if you are checking by hand — 510 minutes minus 45 is 465, and 465 ÷ 60 = 7.75.
The same numbers feed straight into the time duration calculator.
How to use this calculator
Enter your start time, end time and the break in minutes. The result shows decimal hours and hours-and-minutes. To convert the decimal result back to clock format, try the decimal hours to time calculator, or use the add time calculator to combine shifts.
Decimal hours for payroll
Payroll systems usually want decimal hours (8.00, 8.25, 8.50). Each minute is 1/60 of an hour, so 15 minutes is 0.25 and 30 minutes is 0.50. The big number above is already in decimal form, ready to enter on a timesheet.
The full set of quarter-hour values is worth memorising: 15 minutes is 0.25, 30 is 0.50, 45 is 0.75. Other minutes are less tidy — 10 minutes is 0.1667 and 20 is 0.3333 — so keep two decimal places and let the rounding fall where it may rather than rounding each day up to the next quarter hour.
For overnight shifts, split the work either side of midnight and add the two results: 22:00 to 24:00 is 2 hours and 00:00 to 06:00 is 6, giving 8 hours before any break is taken off. Keep a note of the actual clock times as well as the total, since overtime and night-shift premiums usually depend on when the hours fell, not just how many there were.
Once that is settled, the time to decimal calculator takes care of the next part.
Frequently asked questions
- How do I calculate hours worked in a day?
- Subtract your start time from your end time, then subtract your break. For 09:00 to 17:30 with a 30-minute break, that is 8.00 hours.
- Does it subtract my lunch break?
- Yes. Enter your unpaid break in minutes and it is removed from the total before showing your hours worked.
- Can it handle overnight shifts?
- This version assumes start and end are on the same day. For shifts crossing midnight, split them into two same-day entries.
- What is 8 hours in decimal?
- Exactly 8.00. Thirty minutes is 0.50 and fifteen minutes is 0.25, so 8 h 30 min is 8.50 decimal hours.
- Should paid breaks be entered in the break box?
- No — only enter unpaid break time. A paid coffee break stays inside your working hours, so subtracting it would short your own timesheet. In many places a 30-minute unpaid meal break after six hours is the rule, while short rest breaks remain paid.