Work Hours Calculator
Calculate total work hours between a start time and end time, minus breaks. Get results in hours and minutes, decimal hours, and total minutes.
How to Calculate Work Hours
Calculating work time is straightforward once you know the formula:
The formula
Work Time = End Time - Start Time - Break Duration
Example: Start at 8:30 AM, end at 5:15 PM, with a 45-minute lunch break. Total elapsed time = 8 hours 45 minutes. Minus 45-minute break = 8 hours 0 minutes (8.00 decimal hours).
Note your start and end times
Record the exact time you begin and finish work. Use AM/PM format or 24-hour time. Be precise to the minute for accurate payroll.
Calculate total elapsed time
Subtract the start time from the end time. If the shift crosses midnight, add 24 hours to the end time before subtracting.
Subtract break time
Deduct any unpaid breaks (such as lunch). Most 8-hour shifts include a 30-minute or 1-hour unpaid meal break.
Work Time in Decimal Hours
Payroll systems typically require time in decimal format rather than hours and minutes. Converting is simple: divide the minutes by 60 and add to the hours.
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 5 min | 0.08 | 35 min | 0.58 |
| 10 min | 0.17 | 40 min | 0.67 |
| 15 min | 0.25 | 45 min | 0.75 |
| 20 min | 0.33 | 50 min | 0.83 |
| 25 min | 0.42 | 55 min | 0.92 |
| 30 min | 0.50 | 60 min | 1.00 |
For example, 7 hours and 45 minutes = 7 + (45/60) = 7 + 0.75 = 7.75 decimal hours. At $20/hour, that equals $155.00.
Common Work Time Calculations
Reference table for standard shift lengths showing start time, end time, break duration, and the resulting net work time.
| Shift | Start | End | Break | Net Time | Decimal |
|---|---|---|---|---|---|
| 8-hour shift | 9:00 AM | 5:00 PM | 0 min | 8h 0m | 8.00 |
| 8-hour shift + lunch | 9:00 AM | 5:30 PM | 30 min | 8h 0m | 8.00 |
| 8-hour shift + breaks | 8:00 AM | 5:00 PM | 60 min | 8h 0m | 8.00 |
| 10-hour shift | 7:00 AM | 5:30 PM | 30 min | 10h 0m | 10.00 |
| 12-hour shift | 6:00 AM | 6:30 PM | 30 min | 12h 0m | 12.00 |
| Night shift | 10:00 PM | 6:30 AM | 30 min | 8h 0m | 8.00 |
Tracking Work Time Automatically
Manual time calculations work for occasional use, but they introduce errors and take time when done daily across a team. Common issues include forgetting exact start and end times, rounding errors, and inconsistent break tracking.
Automatic time tracking software eliminates these problems by recording clock-in and clock-out times precisely, calculating work hours automatically, and generating timesheets ready for payroll.
Learn more about the benefits of switching from manual to automated tracking in our guide to automated employee time tracking.
Frequently Asked Questions
How do I calculate work time?
Subtract your start time from your end time, then subtract any break time. For example, if you start at 9:00 AM and end at 5:00 PM with a 30-minute lunch break, your work time is 8 hours minus 30 minutes = 7 hours and 30 minutes.
What are decimal hours?
Decimal hours express time as a decimal number instead of hours and minutes. For example, 7 hours and 30 minutes is 7.50 decimal hours. This format is commonly used in payroll systems because it simplifies multiplication with hourly rates.
How do I convert minutes to decimal hours?
Divide the minutes by 60. For example, 45 minutes = 45/60 = 0.75 hours. Common conversions: 15 min = 0.25, 30 min = 0.50, 45 min = 0.75. For payroll, always round to two decimal places.
Does this calculator work for overnight shifts?
Yes. If your end time is earlier than your start time, the calculator automatically detects that the shift crosses midnight and calculates the total time correctly. For example, 10:00 PM to 6:00 AM = 8 hours.
Should I include lunch breaks in work time?
It depends on your employer and local labor laws. In the US, unpaid meal breaks (typically 30 minutes or more) are not counted as work time under the FLSA. Short rest breaks (5-20 minutes) are generally considered paid work time.
How is work time different from hours worked?
Work time and hours worked are often used interchangeably, but "hours worked" in a legal context specifically means time during which an employee is required to be on duty or at a prescribed workplace. Break time, commute time, and on-call time may or may not count depending on the situation.
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Stop Calculating Work Time Manually
HiveDesk tracks work hours automatically with desktop, mobile, and browser apps. Generate accurate timesheets for payroll. $5/user/month, all features included.