Overtime has one formula and a hundred jurisdictional variations. The formula is easy; knowing WHICH rule applies to you is the part that matters — and where generic calculators quietly mislead people.
The formula
Overtime pay = overtime hours x regular rate x multiplier (commonly 1.5)
The variations are in what counts as overtime hours:
- Weekly threshold — hours past a weekly total (40 hours per week under the US federal FLSA; 44 in some Canadian provinces). Common for most hourly jobs.
- Daily threshold — hours past a daily total (some jurisdictions apply 8 hours per day, some do not have daily overtime at all).
- Both — some places apply daily AND weekly rules, paying whichever produces more overtime.
We deliberately do not list a table of statutory thresholds here — rules change, exceptions abound (managerial roles, agriculture, trucking, averaging agreements), and a stale number presented confidently is worse than none. Check your jurisdiction's employment standards site or your agreement.
Worked example: weekly threshold (40 hours)
You worked 46 hours this week at 20 dollars per hour, with a 40-hour weekly threshold and 1.5x multiplier.
- Regular: 40 x 20 = 800
- Overtime: 6 x 20 x 1.5 = 180
- Gross: 980
The weekly time card calculator applies exactly this rule to a full week of daily entries — set your own threshold and multiplier.
Worked example: daily threshold (8 hours)
One 11-hour day at 20 dollars per hour, 8-hour daily threshold, 1.5x.
- Regular: 8 x 20 = 160
- Overtime: 3 x 20 x 1.5 = 90
- Gross: 250
The single-shift calculator handles the daily version, including unpaid breaks before the split.
What to watch for
- The threshold applies to hours WORKED, not hours at the workplace — unpaid breaks come out first.
- The multiplier applies to your regular rate — check how your agreement defines it if you earn premiums or differentials.
- Averaging agreements and exemptions can change everything — the categories exempted from overtime vary widely.
ShiftFlow applies your configured overtime rules to every logged shift automatically and flags paychecks that do not match the hours you actually worked — that is the whole point of the app.