Adding up a time card
Each day's hours are clock-out minus clock-in, minus any unpaid meal break. The week's total is then split into regular and overtime hours. Federal law sets the overtime threshold at 40 hours in a fixed, recurring seven-day workweek; days are never averaged across two weeks, so a 45-hour week followed by a 35-hour week still owes 5 hours of overtime.
The formulas
day hours = (out − in, + 24 h if overnight) − break / 60 weekly rule: overtime = max(0, total − 40) daily rule: overtime = Σ max(0, day − 8) + max(0, (total − daily OT) − 40) gross pay = regular × rate + overtime × rate × 1.5
Worked example
Monday–Friday 9:00 AM – 5:30 PM with a 30-minute lunch is 8 hours a day = 40 hours. Add Saturday 9:00 AM – 2:00 PM (5 hours) for 45 hours.
At $20/hour: 40 × $20 = $800 regular, 5 × $30 = $150 overtime, gross $950.00.
Notes
- The daily rule here is 1.5× after 8 hours; California's double time after 12 hours in a day and on the seventh consecutive day is not included.
- Gross pay is before taxes and deductions; exempt salaried employees are not owed overtime under the FLSA.
Sources: U.S. Department of Labor, Overtime Pay and Fact Sheet #22: Hours Worked under the FLSA; California DIR, Overtime FAQ.
Frequently asked questions
When does overtime start?
Under the federal Fair Labor Standards Act, non-exempt employees earn at least 1.5 times their regular rate for hours over 40 in a workweek. There is no federal daily limit. A few states add daily overtime — California, for example, pays 1.5× after 8 hours in a day (and 2× after 12) — so choose the daily rule if it applies to you.
Do lunch breaks count as hours worked?
Under U.S. Department of Labor rules, bona fide meal periods of 30 minutes or more when you are fully relieved of duty are not work time, so enter them as a break. Short rest breaks of about 5 to 20 minutes are counted as hours worked and paid, so do not subtract them.
How do I enter an overnight shift?
Type the clock-in and clock-out times as they appear on the clock. If clock-out is earlier than clock-in — say 10:00 PM to 6:30 AM — the calculator treats it as ending the next morning and counts 8.5 hours before the break.
How do I convert my hours to decimal for payroll?
Divide the minutes by 60: 37 hours 45 minutes = 37.75 hours. The totals here are shown both ways. Some employers round punches to the nearest quarter hour; the DOL allows this only if it averages out and does not consistently underpay.