How to Calculate Work Hours
Calculating work hours is simple when you know your start time, end time, and unpaid break duration. The basic idea is to find the total time between clock-in and clock-out, then subtract any unpaid breaks.
Work Hours Formula
Use this formula:
Example:
Start time: 9:00 AM
End time: 5:00 PM
Break: 30 minutes
The shift duration is 8 hours. After subtracting the 30-minute break, the total worked time is 7 hours and 30 minutes.
Example Calculation
| Start Time | End Time | Break | Total Worked |
|---|---|---|---|
| 9:00 AM | 5:00 PM | 30 minutes | 7h 30m |
| 8:00 AM | 4:30 PM | 45 minutes | 7h 45m |
| 1:00 PM | 5:00 PM | 0 minutes | 4h 00m |
Decimal Hours for Payroll
Payroll systems often use decimal hours instead of hours and minutes.
Examples:
- 15 minutes = 0.25 hours
- 30 minutes = 0.50 hours
- 45 minutes = 0.75 hours
So 7 hours and 30 minutes becomes 7.50 hours.
Common Mistakes to Avoid
- Forgetting to subtract unpaid breaks.
- Mixing AM and PM times.
- Entering break time as hours instead of minutes.
- Rounding too early before calculating totals.
- Using decimal hours incorrectly.
Use the Work Hours Calculator
You can use our free Work Hours Calculator to enter your start time, end time, and breaks. It calculates your total worked time in both hours/minutes and decimal format.
Related calculators
Related guides
How to Calculate Lunch Breaks in Work Hours
Learn how lunch breaks are deducted from work hours and timesheet totals.
Timesheet Basics for Employees
A simple guide to recording daily work hours, breaks, overtime, and weekly totals.
Decimal Hours Chart
Convert minutes to decimal hours with a simple reference chart for payroll and timesheets.
Frequently Asked Questions
If your lunch break is unpaid, subtract it from your total shift duration.
7 hours and 30 minutes equals 7.50 decimal hours.
Yes. If a shift starts at night and ends the next day, use a calculator that supports overnight shifts or includes a date field.
Use the Work Hours Calculator
Enter your start time, end time, and breaks to get total worked time instantly.