If you just want the number, the overtime calculator splits your hours into regular and overtime and works out the pay. This guide explains the rules behind it, so you can check a paycheck or do the math yourself.
When overtime starts: the 40-hour week
Under the US Fair Labor Standards Act, non-exempt employees earn at least 1.5 times their regular rate for every hour over 40 in a workweek. Federal law has no daily limit — a 10-hour day isn't overtime on its own if the week stays at 40 or under.
Each workweek stands alone. A 35-hour week followed by a 45-hour week earns 5 hours of overtime, not zero — employers can't average the two. The workweek is any fixed, recurring 7-day period; it doesn't have to run Sunday to Saturday.
Example: 46 hours at $20/hour
Total: $980
Daily overtime: California and a few other states
Some states add a daily rule on top of the weekly one. California is the best known: over 8 hours in a workday earns 1.5×, and over 12 hours earns double time. Under a daily rule, a 10-hour day is 8 regular hours and 2 overtime hours — even in a week that totals 40.
That difference is bigger than it looks. Four 10-hour days add up to exactly 40 hours: no overtime under the federal weekly rule, but 8 overtime hours under California's daily one.
Example: a 13-hour day in California at $20/hour
Total for the day: $320
Minutes become decimal hours first
Pay is calculated in decimal hours, so convert minutes before multiplying: divide by 60. A week of 42 hours 45 minutes is 42.75 hours, which makes 2.75 overtime hours. At $18/hour that's 2.75 × $27 = $74.25 in overtime. The decimal hours converter has the full minutes-to-decimal chart.
Double time, holidays, and weekends
Outside a handful of state rules like California's, double time and holiday or weekend premiums usually come from your contract or employer policy rather than federal law. If yours pays double after a set number of hours, the calculation is the same — just change the multiplier and the threshold.
Who isn't owed overtime
Many salaried employees are classified as exempt and aren't entitled to overtime pay. Whether you're exempt depends on your duties and salary, not just your job title. Rules also vary by state and contract, so treat this guide as the arithmetic, not legal advice.
Do it in the calculator
Add up the week's shifts in the work hours calculator, then enter the total in the overtime calculator. Its threshold and multiplier default to 40 hours and 1.5× and can be changed to match your rules. To check a single day under a daily rule, set the threshold to 8. It applies one overtime rate at a time, so for a day past 12 hours, work out the double-time hours separately.