How to calculate overtime pay

Overtime pay sounds simple — time-and-a-half after 40 hours — and it almost always turns out to be more complicated than that. Federal rules are one layer. State rules can stack on top. Shift differentials, double-time thresholds, salaried non-exempt classifications, and paid leave all introduce edge cases that can swing a paycheck by hundreds of dollars. This guide walks through the math that actually governs your OT check and how to verify it.

The federal baseline: the FLSA 40-hour rule

The Fair Labor Standards Act (FLSA) — the federal wage-and-hour law — requires employers to pay non-exempt workers at least 1.5 × their regular rate for every hour over 40 in a workweek. That’s the floor. Your state may require more; it can’t require less.

A workweek is any fixed, recurring 168-hour period — doesn’t have to be Monday–Sunday. Your employer picks it and has to keep it consistent. Days off don’t count against the 40 threshold, and federal law does not require daily overtime or double-time.

State rules that stack on top

California is the strictest: time-and-a-half after 8 hours in a day and after 40 in a week (whichever hits first), double-time after 12 hours in a day, and double-time for hours 9+ on a seventh consecutive workday. A 14-hour shift in California generates 8 hours regular, 4 hours at 1.5×, and 2 hours at 2×.

Colorado has daily OT after 12 hours (not 8). Alaska has daily OT after 8 hours. Nevada has daily OT after 8 hours only for workers making less than 1.5× the state minimum wage. Every other state defaults to the federal 40-hour rule unless a union contract says otherwise.

Time-and-a-half vs double-time — the math

Time-and-a-half = 1.5 × base rate. On $22/hour, that’s $33/hour. A 45-hour week at $22 pays 40 × $22 + 5 × $33 = $880 + $165 = $1,045 gross — not 45 × $22 = $990.

Double-time = 2 × base rate. $22/hour becomes $44/hour. Only triggered by state rules (California 12+/day, 7th-day 9+ hours) or union contracts. Federal law alone never mandates double-time.

The overtime calculator handles federal, California, and custom rule sets including the daily-plus-weekly stacking that trips most payroll software up.

Paid leave doesn’t count

Federal law counts only hours worked toward the 40-hour OT threshold. If you work 32 hours and take 16 hours of PTO, your check shows 48 hours but you’re owed zero overtime. Some states and union contracts override this — read the fine print.

Same story with holidays. Working on a company holiday doesn’t automatically trigger overtime or holiday pay premiums under federal law. Any holiday 1.5× or 2× premium is contractual, not statutory.

The salaried non-exempt trap

If you’re salaried but non-exempt (paid a fixed weekly amount, but classified hourly for OT purposes), you’re still owed overtime. The math: weekly salary ÷ 40 = implied regular rate. Hours over 40 get 1.5× that implied rate.

On a $1,000/week salary: $1,000 ÷ 40 = $25/hour regular. A 50-hour week pays $1,000 + 10 × $37.50 = $1,375. Some employers use the “fluctuating workweek” method (FLSA § 778.114) which lowers the OT premium to 0.5× (since the salary already covers straight-time for all hours) — that’s legal but has to meet specific conditions including a written agreement.

How to verify your paycheck

Pull your last pay stub. Find: hours worked that week, regular rate, overtime hours, overtime rate, and gross pay. Plug the first four into the overtime calculator with your state’s rule set. If the gross matches within a dollar, you’re fine. If it doesn’t, print the calculator’s breakdown and show it to HR — payroll software gets this wrong often enough that checking is worthwhile.

Common error patterns: OT calculated on base rate when a shift differential should have been included (differentials count toward “regular rate” under FLSA), daily-plus-weekly double-counting in California, and salaried non-exempt workers getting zero OT because someone in payroll treated them as exempt. All three are worth catching.

If you suspect wage theft

Document everything — shift logs, pay stubs, schedule emails, Slack messages. Start with HR or payroll politely; most cases are honest errors. If that doesn’t resolve it, the US Department of Labor Wage and Hour Division accepts confidential complaints and investigates without cost to you. State labor boards often recover wages faster than federal.

Pair the overtime calculator with our paycheck calculator to model take-home after taxes, or the hourly rate calculator to figure out what your real per-hour number looks like factoring in benefits and PTO.