9:00 AM to 5:30 PM is 8.5 elapsed hours; subtracting a 30-minute unpaid break leaves 8.0 hours worked.
The basic hours-worked formula
To calculate hours worked, subtract the start time from the end time, then subtract any break time that should not be counted. In simple form: Hours worked = clock-out time − clock-in time − excluded break time.
Keep the time units consistent. If you calculate in minutes first, divide total minutes by 60 to convert the final result to decimal hours. The arithmetic tells you elapsed work time; whether a specific break or activity is compensable can depend on applicable rules and the facts.
How to calculate hours worked step by step
Write down the start time and end time, convert both to a common format, find the elapsed time, subtract any excluded break, and convert the remainder to the format you need. Using minutes often prevents AM/PM and decimal-time mistakes.
- 1. Record clock-in and clock-out times.
- 2. Convert the times to minutes after midnight or another consistent time scale.
- 3. Subtract start from end to get elapsed time.
- 4. Subtract any break time that is excluded from hours worked.
- 5. Convert the remaining minutes to hours and minutes or decimal hours.
Example: 9:00 AM to 5:30 PM with a 30-minute break
From 9:00 AM to 5:30 PM is 8 hours 30 minutes, or 510 minutes. Subtract a 30-minute break and the result is 480 minutes. Divide 480 by 60 and the final result is 8.00 hours worked.
This is a time calculation example. In real payroll situations, whether a meal or rest period can be excluded from compensable time depends on the circumstances and applicable law.
How do you calculate an overnight shift?
When a shift crosses midnight, treat the end time as occurring on the next day. For example, 10:00 PM to 6:00 AM is eight elapsed hours. Subtract a 30-minute excluded break and the result is 7 hours 30 minutes.
A simple way to avoid negative results is to convert the clock-out time to a next-day value. In minutes after midnight, 10:00 PM is 1,320 and 6:00 AM on the next day can be treated as 1,800. The difference is 480 minutes.
How to convert worked minutes to decimal hours
Decimal hours are not written like clock time. Divide the minutes portion by 60, then add it to the whole hours. Thirty minutes is 0.50 hours, 15 minutes is 0.25 hours, and 45 minutes is 0.75 hours.
If the result is 7 hours 30 minutes, the decimal result is 7.50, not 7.30. For a reference table and more examples, see Decimal Hours Explained or use the Decimal Hours Calculator.
| Hours and minutes | Decimal hours |
|---|---|
| 7:15 | 7.25 |
| 7:30 | 7.50 |
| 7:45 | 7.75 |
| 8:00 | 8.00 |
Which breaks count as hours worked?
The U.S. Department of Labor explains that short rest periods, usually 20 minutes or less, are generally counted as hours worked under the federal FLSA. Bona fide meal periods, typically 30 minutes or more, generally do not have to be counted when the employee is completely relieved from duty.
Do not use a time calculator by itself to decide whether a particular break is legally unpaid. A calculator can subtract the minutes you enter, but classification of the time may require employer policy, state law, or federal wage-and-hour rules.
Common mistakes when adding work hours
Common errors include treating clock minutes as decimals, forgetting to move an overnight clock-out time to the next day, subtracting paid breaks as if they were unpaid, and rounding each segment before the final total.
For multiple clock-in and clock-out segments, calculate each segment separately and add the results. If you need a quick single-shift result, use the Hours Worked Calculator; for a time-card style result with decimal output, use the Time Card Calculator.
Use the calculator when you want the result instantly
The Hours Worked Calculator is the fastest option for a start time, end time, and break. The Time Card Calculator is useful when you want the result displayed in hours, minutes, and decimal hours.
These tools perform the arithmetic you provide. They do not determine whether time is legally compensable or how an employer must classify a break.
Continue with a calculation