Basic work-hours formula
Example workday
If work begins at 9:00 AM and ends at 5:30 PM, the elapsed period is 8 hours 30 minutes. Subtracting a 30-minute unpaid break leaves 8 hours worked.
Convert minutes to decimal hours
Payroll systems often express time in decimal hours. Divide the number of minutes by 60 and add the result to the whole hours.
For example, 7 hours 30 minutes equals 7.5 decimal hours.
Shifts that cross midnight
An overnight shift ends on the following calendar day, so the calculation must account for the date change rather than treating the end time as earlier than the start time.
Paid vs unpaid breaks
Only breaks that should be excluded from paid working time should be deducted. Whether a break is paid depends on the applicable employment rules and workplace policy.
Common timesheet mistakes
- Treating 30 minutes as 0.30 hours instead of 0.50 hours
- Forgetting to subtract unpaid breaks
- Mishandling overnight shifts
- Mixing 12-hour and 24-hour time formats
- Rounding individual entries inconsistently
A calculator can determine elapsed time, but overtime, break entitlement and rounding rules depend on workplace policy and applicable law.