How to Calculate Hours Worked
Adding up hours sounds trivial until you're staring at a stack of time cards with 8:47 starts and 5:12 finishes. Here's the clean way to do it, by hand or with a calculator.
The three steps
1) Find the elapsed time between clock-in and clock-out for each day. 2) Subtract unpaid breaks. 3) Convert leftover minutes to decimal (divide by 60) and total the week.
Example: in at 8:30 AM, out at 5:00 PM with a 30-minute unpaid lunch. Elapsed time is 8.5 hours; minus 0.5 for lunch leaves 8.0 hours worked.
Converting minutes to decimals
Payroll runs on decimal hours, not hours-and-minutes. Divide minutes by 60: 15 minutes = 0.25, 20 minutes = 0.33, 45 minutes = 0.75. So 38 hours 45 minutes is 38.75 on the timesheet.
A common mistake is typing 8 hours 30 minutes as '8.30' — that's 8 hours 18 minutes in decimal. It's 8.50.
Overnight shifts and rounding
For shifts that cross midnight, count straight through — in at 10 PM, out at 6 AM is 8 hours, usually attributed to the day the shift started unless your policy says otherwise.
If you round punches, federal rules require it to be neutral (the familiar 7-minute rule for quarter-hours). Always keep the actual punch times too.
FAQ
How do I calculate hours worked with a lunch break?
Take the time between clock-in and clock-out, then subtract the unpaid lunch. An 8 AM to 4:30 PM day with a 30-minute unpaid lunch is 8 hours worked.
What is 7.5 hours in hours and minutes?
7 hours 30 minutes. Multiply the decimal portion by 60 to get minutes (0.5 × 60 = 30).
Track hours the easy way — free
Kloqk is a free time clock that handles hours, overtime, and payroll-ready exports.
Start free