Methodology

Gross pay is computed first, with no tax rules involved: regular hours, overtime hours at your multiplier, tips for the period, and the per-period share of any annual bonus. Qualifying pre-tax deductions reduce the applicable taxable wages: retirement and health deductions do not necessarily reduce the same tax bases. Federal withholding, Social Security and Medicare, state and local amounts are calculated with the applicable state dependencies. Alabama uses a federal-withholding deduction; Massachusetts uses a limited contribution deduction in its annual planning method. Post-tax deductions come off last to reach net pay.

Registered state estimates currently cover New York, California, Texas, Florida, New Jersey, Illinois, Pennsylvania, Ohio, Georgia, North Carolina, Maryland, Virginia, Michigan, Arizona, Tennessee, Washington, Indiana, Missouri, Wisconsin, Colorado, Minnesota, South Carolina, Alabama, Massachusetts, Nevada, South Dakota, Idaho, Arkansas, Nebraska, Oklahoma, Alaska, Mississippi, Vermont, Rhode Island, West Virginia, Hawaii, Connecticut, Kansas, Utah, North Dakota, Montana, Iowa, Louisiana, Kentucky, Wyoming, New Hampshire. Registration does not mean every local tax, deduction or payroll situation is covered. See the current rule citations and verification status on the Data sources page.

Pennsylvania local EIT and Ohio municipal and school-district taxes require you to enter the applicable rates; the calculator does not look them up from an address. Maryland county tax uses your selected county and residency. Michigan city withholding is limited to the registered Detroit options and your selected residency and work percentage.

Federal W-4 Step 4(a) adjusts federal withholding. Interest, dividends or other nonwage income entered there do not become wages paid by your employer for state, city or county withholding. State certificate elections and extra state withholding remain separate. Alabama’s deduction for federal withholding can change its state result when federal withholding changes; this does not turn nonwage income into state payroll wages. This does not calculate state tax due on all your income.

Rules belong to a specific tax year and jurisdiction. Federal, state and local amounts can use different wage bases, certificates and bonus methods. The English and Spanish calculators share the same calculation rules; changing the language does not change the estimate. Select the state and review its scope before using a result.

Content updated October 19, 2026. The sources directory shows the actual review date for each registered state’s rules. Reviewing a publication is not agency endorsement, professional review of your case or a guarantee of complete payroll coverage.

Massachusetts uses the annual column of Circular M for planning, rather than every literal payroll-period factor or actual YTD crossing. South Carolina uses the posted payroll withholding table and distinguishes it from the final-return reform. State certificates and separate bonus methods apply only where the calculator offers them.

Washington, Colorado, Minnesota and Massachusetts employee programs have independent wage bases, caps and coverage selections. An income-tax exemption or reciprocity choice does not automatically remove an employee premium. An employer-funded or private-plan arrangement needs the applicable coverage selection; the calculator does not infer eligibility.

Additional Medicare paycheck withholding uses one employer's annual Medicare wages above $200,000 regardless of filing status. Final-return liability thresholds differ by filing status and remain separate in annual tax-comparison tools. These are annualized estimates; actual YTD threshold crossing and multiple-employer reconciliation are not modeled.

Only employee-paid amounts reduce take-home pay. Employer taxes are deliberately excluded everywhere: California Unemployment Insurance and the Employment Training Tax, Texas unemployment and franchise tax, Florida reemployment tax, and New Jersey's employer unemployment, employer disability and municipal employer payroll taxes.

State and city withholding uses annual rate schedules applied to annualised pay rather than each state's own per-payroll tables, so an employer's per-paycheck state withholding can differ. Federal bonuses use the selected supplemental method. New York State withholding uses the published 2026 annual Methods II/III, your IT-2104 status, allowances and extra withholding. A separately paid or identified NY bonus can use the 11.70% option only when regular NY withholding is confirmed; otherwise the aggregate method is used. Combined pay remains annualized. Bonus tax is counted once and shown as a pay-period average, not the actual bonus check. Printed per-payroll withholding tables may differ slightly from the annual schedule's rounded amounts. Final-return benefit recapture, credits and multiple-job reconciliation are not modeled. NYC residents use the NYS-50-T-NYC annual payroll withholding schedule, separate IT-2104 line 2 allowances and line 4 extra withholding. Identified bonuses can use 4.25% only with regular NYC withholding confirmed independently of NY; otherwise NYC uses the aggregate estimate. Final-return NYC brackets and credits are separate from this paycheck calculation. New York paid family leave and standard disability contributions are optional annualized estimates, selected only when employee-paid; exact YTD cap stopping and irregular employment are not modeled; the Yonkers surcharge is not modelled; contributions with a wage ceiling spread evenly across the year rather than stopping mid-year; no credits beyond those you enter.

The English paystub builder also offers restricted, confirmed NY benefit treatment for ordinary wages without a bonus. Employee traditional 401(k) deferrals reduce income-tax wages but remain FICA wages; qualifying Section 125 health premiums reduce income-tax and FICA wages. These amounts must exactly match all current pre-tax deduction rows and be confirmed with payroll. PFL still uses gross; gross and deduction totals are unchanged. No eligibility is inferred from labels. Other states, Roth, other fringe benefits, NYC government IRC 125 programs, public 414(h) pensions, plan/owner exceptions and bonus allocation require actual payroll values. Payment, employee, earnings or deduction changes require confirmation again; YTD remains separately entered.

The paystub builder uses these automatic tables only for payments dated in 2026. Georgia's registered method starts May 11, 2026, and Ohio's starts August 1, 2026. Earlier payments require actual payroll values; changing a document's pay date does not select an unregistered historical table. The free annual calculators estimate the currently registered method and do not reproduce every earlier paycheck.

For NY paystubs, NYC payroll residence must be selected explicitly for the payment. Work city and mailing address do not establish residence. NYC residents have city withholding even when working elsewhere in NY; ordinary nonresidents do not have NYC resident withholding simply because they work in the city. Section 1127 city-employee payments, Yonkers, residence changes and interstate allocation require actual payroll values. This selection does not determine legal residence or verify an employee's address.

The English paystub builder separately offers optional prior same-employer 2026 payroll inputs for the current payment. After explicit confirmation, Social Security uses the remaining annual wage base, Medicare uses current wages and only the portion crossing the employer withholding threshold, and selected NY PFL uses the remaining premium cap. These inputs are never inferred from displayed YTD or loaded from an account. Employer or employee identity changes require confirmation again. Manual deduction classifications do not establish taxable exclusions: enter actual payroll values when benefit or coverage exceptions apply. The free annual calculators retain annual-average caps; DBL, other state contributions, irregular periods and multi-employer reconciliation are not newly covered. Displayed YTD must still be entered and checked separately.

The paystub builder also offers a separate optional standard NY DBL weekly allocation. Payroll must confirm consecutive employer-week boundaries, gross wages allocated to each week, standard employee-paid coverage and no other wages or DBL collections for those weeks. Weekly gross totals must match this payment exactly, before benefit deductions. Each confirmed week's estimate is 0.5% of its gross wages, capped at $0.60; unpaid weeks add zero. This does not model catch-up collections, enhanced plans, other payments in those weeks or multiple-employer adjustments. Off keeps the annual-average method. The free calculators are unchanged, and displayed YTD remains separately entered and checked.

California withholding follows Form DE 4 and the Method B steps in order: the Table 1 low income exemption, the Table 2 estimated deduction for additional allowances, the Table 3 standard deduction, the Table 5, 6 or 7 rate schedule, then the Table 4 credit for regular allowances only. The marital-status table and both allowance counts are entered on screen.

New Jersey withholding follows Form NJ-W4. All five published rate tables — A, B, C, D and E — are modelled, and the NJ-W4 Instruction A Wage Chart can select the letter for you from your own wages and all other household wages. Each exemption claimed removes the published $1,000 annual allowance from wages before the rate table is applied.

Language models are never used to compute a tax amount. A future explanation layer may describe results that the deterministic engine has already produced, and nothing more.