Calculation methodology

How MyNetPay estimates take-home pay

The calculator is a planning model built from structured tax data. It does not reproduce an employer’s full payroll system or replace professional advice.

Calculation order

1. Annualize regular pay based on the selected income type, hours, and weeks.
2. Add bonus and overtime income.
3. Subtract eligible user-entered pre-tax deductions for income-tax purposes.
4. Apply the 2026 federal standard deduction for the selected filing status, then calculate progressive federal income tax.
5. Apply the modeled state deduction and resident wage-income schedule.
6. Calculate employee Social Security tax up to the $184,500 wage base.
7. Calculate Medicare and, where applicable, Additional Medicare Tax liability.
8. Apply a user-entered local wage-tax rate, post-tax deductions, and additional withholding.

What is included

Regular wages, bonus income, overtime, traditional 401(k) contributions, health-insurance deductions, other pre-tax and post-tax deductions, a user-entered local rate, federal income tax, modeled resident state income tax, Social Security, Medicare, and Additional Medicare Tax.

What is not included

Dependents, most credits, itemized deductions, multi-job Form W-4 adjustments, nonresident or part-year rules, reciprocity, unemployment insurance, most state payroll programs, garnishments, stock compensation, tips and overtime deductions under special federal rules, employer benefits, and automatic city/county tax lookup.

Filing status

Federal brackets and standard deductions use the selected filing status. State sources commonly publish single and joint schedules; head-of-household and married-filing-separately state estimates use the single schedule unless a dedicated rule is encoded.

Why an employer result can differ

Employers calculate withholding per pay period using Form W-4 and Publication 15-T rather than simply dividing projected annual tax. Year-to-date wages, benefit plan treatment, pay-period rounding, state withholding certificates, local jurisdiction rules, and supplemental-wage methods can all change a paycheck.

Review cadence

Federal and state files contain a tax year and last-verified date. They should be reviewed when an authority publishes a new annual table or when legislation changes a rate. A changed date is published only after the data is actually reviewed.

Informational-use notice

Results are estimates for informational planning. They are not tax, legal, payroll, investment, or financial advice. Compare important decisions with your pay stub, official calculators, or a qualified professional.

Found an issue? Report the calculation and cite the official source.