How We Calculate: Methods and Sources

Where the calculation happens

Calculations run in your browser. The rules, rates and thresholds described on this page are built into each calculator when the site is published, so a result needs no server: when you change a figure, your device works it out with the same code that produced the worked examples on each page. Nothing you type is sent to a server while you calculate, and once a page has loaded the calculator keeps working without a connection.

Money and rounding

Each line of a result is worked out in dollars and rounded to the cent, with halves rounded away from zero. Totals add the rounded lines, so every line on the stub adds up to the total shown. Hourly rates are shown to as many as four decimal places when a salary or bonus produces one, because rounding a rate early shifts every line built on it.

Time and a half and double time

The overtime rate is the regular hourly rate times the multiplier: 1.5 for time and a half, 2 for double time. A salary is turned into an hourly rate by dividing the annual salary by 52 times the weekly hours it covers. Pay for the hours is hours × rate for each line.

Weekly overtime

Hours are sorted day by day. Where a state has a daily or seventh-day rule, it is applied first. The weekly threshold is then applied in day order, counting only hours not already paid as overtime, so no hour is paid as overtime twice. This gives the same result as paying whichever of the daily or weekly total is greater, which is how several states describe it.

The regular rate follows the FLSA: straight-time earnings plus any nondiscretionary bonus earned in the week, divided by all hours worked (29 CFR 778.109 and 778.209). The stub shows overtime at 1.5 or 2 times the base rate, and a separate line for the extra overtime the bonus creates: the bonus per hour × 0.5 for each overtime hour, and × 1 for each double-time hour.

For a salaried non-exempt employee, the base rate is the weekly salary divided by the hours it is meant to cover (29 CFR 778.113). Hours between that figure and the overtime threshold are paid at the base rate.

State conditions the calculator applies: Nevada’s daily rule only below its rate ceiling, Alaska’s daily rule on the assumption that the employer has four or more employees, Kentucky’s seventh-day rule only in weeks over 40 hours, and Oregon’s manufacturing rule as a separate choice. Alternative workweek schedules, union agreements and industry wage orders are described on the state pages but not applied.

PTO and vacation accrual

Per-hour plans earn the stated hours for each hours worked, using hours per week × 52 ÷ pay periods a year for the hours in each period. Yearly plans divide the allowance by pay periods. Front-loaded plans add the whole allowance at the start of each plan year.

Each pay period, the accrual is added, then any planned time off (spread evenly across the periods), then the year-end reset is applied. A cap stops accrual at the cap and counts what would have been earned above it as lost. A carryover limit removes anything above the limit at the plan-year reset and counts it as lost. The table under the chart shows every period.

PTO payout and withholding

The payout is unused hours × hourly rate (for a salary, annual salary ÷ 52 × weekly hours). Withholding assumes the payout is supplemental wages paid on top of regular pay, as IRS Publication 15 allows: federal income tax at 22% (37% on supplemental wages over $1,000,000 in the year), Social Security at 6.2% up to the $184,500 wage base counting wages already paid this year, and Medicare at 1.45%, plus 0.9% on wages over $200,000. State and local income tax are not estimated.

Overtime deduction

Qualified overtime is the half-time premium on hours over 40 in a workweek, as 26 U.S.C. § 225 defines it. From hours, it is regular rate × 0.5 × overtime hours; from total time-and-a-half pay, it is one third of that pay. It is capped at $12,500 ($25,000 on a joint return), then reduced by $100 for each full $1,000 of modified adjusted gross income over $150,000 ($300,000 joint). Married filing separately gives zero. The tax saved is the deduction × the bracket you pick; if the deduction moves you into a lower bracket, the real saving is a little less.

State rules

Each state rule was researched from its statute, regulation or labor department page and last checked on September 25, 2026. Every state page shows how its rule was checked:

Checked against the full official text: the source was read in full.
Checked against excerpts of the official source: the rule matches excerpts of the official page, but its full text was not read.
No state statute on this subject: the state has no law to cite, so federal law or the employer’s policy decides.

Federal figures, including the payroll tax rates and the deduction limits, were read from their primary sources on September 25, 2026. The rules are code, not text typed into pages: when one changes, every page that uses it changes with it.

What the calculators do not do

Decide whether you are exempt from overtime. That depends on your duties as well as your pay.
Blend two or more pay rates in one week (29 CFR 778.115), tips and tip credits, or piece rates.
Apply city or county rules, or rules for public-sector employees.
Estimate state income tax, or your full federal tax bill.

How we calculate