How to calculate payroll hours
These steps show the US federal rule. If you choose another rule, the tool uses that rule instead.
- Total each employee's hours for each workweek in the pay period.
- For each workweek, hours up to 40 are regular and hours over 40 are overtime.
- Add the workweeks together for the period's regular and overtime hours.
- Convert minutes to decimal hours (divide by 60) before entering them in payroll.
Overtime hours = hours over 40, counted for each workweek on its own
Payroll hours = regular hours + overtime hours
A workweek is a fixed, recurring run of 168 hours that the employer sets. It can start on any day and at any hour, and it can be changed only if the change is meant to be permanent and not to avoid overtime.
29 CFR 778.104, 778.105.
Worked example
Three employees on a biweekly payroll. Ben works 30 hours in week 1 and 50 in week 2.
| Employee | Week 1 | Week 2 | Regular | Overtime | Gross |
|---|---|---|---|---|---|
| Ana, $20.00 | 40 | 40 | 80 | 0 | $1,600.00 |
| Ben, $18.00 | 30 | 50 | 70 | 10 | $1,530.00 |
| Cleo, $25.00 | 45.5 | 38 | 78 | 5.5 | $2,156.25 |
| Pay period | 115.5 | 128 | 228 | 15.5 | $5,286.25 |
Ben averages 40 hours a week, but each workweek stands alone. Week 2 has 10 overtime hours: 30 × $18.00 + 40 × $18.00 + 10 × $27.00 = $1,530.00. Counting the two weeks as one 80-hour block would have paid him $1,440.00, which is $90.00 short.
Hours in each pay period
A full-time schedule of 40 hours a week is 2,080 hours a year (40 × 52). Divided by the number of pay periods:
| Pay period | Periods a year | Standard hours |
|---|---|---|
| Weekly | 52 | 40.00 |
| Biweekly | 26 | 80.00 |
| Semi-monthly | 24 | 86.67 |
| Monthly | 12 | 173.33 |
Semi-monthly and monthly periods do not line up with workweeks, so a workweek can start in one pay period and end in the next. Overtime is still counted on the whole workweek. That is why this calculator takes hours by workweek and offers weekly and biweekly periods, where the weeks fit exactly. The semi-monthly vs biweekly guide shows how many hours each 2027 semi-monthly period really holds.
Rounding clock times
Employers may round clock-in and clock-out times to the nearest 5 minutes, tenth of an hour or quarter hour, as long as the rounding does not end up underpaying employees over time.
29 CFR 785.48(b).
Questions
How many hours is a semi-monthly pay period?
86.67 hours on average for a 40-hour schedule: 2,080 hours a year divided by 24 periods. The real figure depends on how many workdays fall in that half-month.
How do I convert minutes to decimal hours for payroll?
Divide the minutes by 60: 15 minutes is 0.25 and 45 minutes is 0.75, so 7 hours 20 minutes is 7 + 20 ÷ 60 = 7.33 hours. The calculator accepts either form.
Sources
- 29 CFR 778.104, Each workweek stands alone (eCFR)
- 29 CFR 778.105, Determining the workweek (eCFR)
- U.S. Department of Labor, Wage and Hour Division: Overtime Pay
- 29 U.S.C. 207, Maximum hours
- 29 CFR 785.48, Use of time clocks (eCFR)
- Tested against
- Published test cases
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