Shift duration
Shift duration equals end time minus start time, less the unpaid break. If the end time is earlier than the start time, the calculator assumes the shift crosses midnight and adds 24 hours before subtracting the break.
Decimal hours
Minutes are divided by 60. For example, 30 minutes = 0.50 hours and 15 minutes = 0.25 hours.
Overtime
The weekly calculator does not decide which overtime law applies. It uses the threshold and multiplier entered by the user. Regular hours are the smaller of total hours and the threshold. Overtime hours are any hours above the threshold.
Gross pay
Regular pay = regular hours × hourly rate. Overtime pay = overtime hours × hourly rate × overtime multiplier. Gross pay is the sum of those values and does not include taxes, deductions, benefits, bonuses, shift penalties or other payroll adjustments.
Rounding
The current version does not round clock times. That is deliberate: time-rounding rules can depend on the employer, jurisdiction and applicable wage rules. The calculator uses the exact minute values entered.
Dates and saved periods
Weekly periods begin on Monday. Selecting a date in another part of the week moves it to that week’s Monday. Biweekly periods cover 14 days, with overtime calculated separately for the first and second seven-day blocks. Changing dates loads that period’s saved entries or starts a blank card with the current pay settings.
Time limitations
Identical start and end times mean zero hours. Calculations use wall-clock time and do not adjust for daylight-saving changes or time-zone changes. Shifts longer than 24 hours are not supported. Invalid or incomplete shifts must be corrected before a total can be exported.
See worked examples for daytime, overnight and weekly hours.
Sources for U.S. work-hour examples
The calculators are arithmetic tools. When a page mentions U.S. federal overtime or break treatment, the supporting references are the U.S. Department of Labor.
These sources do not mean every worker is covered by the same rule. Exemptions, state laws, collective agreements and employer policies can change the answer.