Work Hours Calculator
Free work hours calculator: enter your start and end time and unpaid break to get total hours worked, decimal hours, and pay. Handles overnight shifts.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the steps
How the Work Hours Calculator Works
This calculator turns clock-in and clock-out times into the numbers payroll actually uses: total hours worked, decimal hours, and pay. Enter your start time, end time, an unpaid break in minutes, and an optional hourly rate, and it updates instantly.
How it works
The tool first finds the time between your start and end:
Minutes on the clock = (end hour × 60 + end minute) − (start hour × 60 + start minute)
If the result is negative the shift crossed midnight, so 24 hours (1,440 minutes) is added. It then subtracts your unpaid break and divides by 60:
Hours worked = (minutes on the clock − unpaid break) ÷ 60 Pay = hours worked × hourly rate
Worked Example
Suppose you start at 9:00, finish at 17:30, take a 30-minute unpaid lunch, and earn $20/hour:
- Time on the clock = 17:30 − 9:00 = 8.50 hours (510 minutes)
- Minus break = 510 − 30 = 480 minutes = 8.00 hours
- Pay = 8.00 × $20 = $160.00
Why Decimal Hours Matter
Payroll software multiplies a decimal number of hours by your rate, so 8 hours 30 minutes must become 8.50, not 8.30. The most common conversions:
| Minutes | Decimal hours |
|---|---|
| 15 | 0.25 |
| 30 | 0.50 |
| 45 | 0.75 |
| 10 | 0.17 |
| 20 | 0.33 |
Tips for Accurate Timesheets
- Log to the minute. Rounding each entry to the nearest quarter-hour can quietly cost you (or your employer) money over a month.
- Separate paid and unpaid breaks. Only unpaid breaks should be deducted from worked hours.
- Watch overnight shifts. This tool handles a single shift that crosses midnight automatically; split multi-day totals into one row per shift.
Frequently asked questions
How do I calculate total hours worked?+
Subtract your start time from your end time to get the time on the clock, then subtract any unpaid break. For a 9:00 to 17:30 shift with a 30-minute lunch, that is 8.5 hours minus 0.5 hours = 8.0 hours worked.
How does the calculator handle overnight shifts?+
If the end time is earlier than the start time, the tool assumes the shift crosses midnight and adds 24 hours. A 22:00 to 06:00 shift is counted as 8 hours rather than a negative number.
What are decimal hours and why do payroll systems use them?+
Decimal hours express minutes as a fraction of an hour, so 8 hours 30 minutes becomes 8.5. Payroll multiplies decimal hours by the hourly rate, which is cleaner than working with hours-and-minutes.
Should I deduct my lunch break from hours worked?+
Deduct any unpaid break, such as an unpaid lunch, because you are not paid for that time. Paid rest breaks stay in your total. Enter only the unpaid minutes in the break field.
How do I convert minutes to decimal hours?+
Divide the minutes by 60. So 15 minutes is 0.25, 30 minutes is 0.50, and 45 minutes is 0.75. Add this to the whole hours to get decimal hours for payroll.