Exactly how our paycheck calculators turn your inputs into an estimate, which rules they use and where those rules come from. Tax year: 2026.
1. Gross Pay per Paycheck
Salary: gross pay per paycheck = annual salary ÷ pay periods per year.
Hourly: gross pay per paycheck = hourly rate × hours per week × 52 ÷ pay periods per year.
| Pay frequency | Pay periods per year |
|---|---|
| Weekly | 52 |
| Bi-weekly | 26 |
| Semi-monthly | 24 |
| Monthly | 12 |
2. Pre-Tax Deductions
Traditional 401(k) contributions reduce wages subject to federal income tax, but not Social Security or Medicare. Health insurance premiums and HSA contributions made through an employer’s cafeteria plan reduce wages for income tax, Social Security and Medicare. “Other deductions” are treated as after-tax.
3. Federal Income Tax Withholding
We follow the IRS percentage method in Publication 15-T for 2026, for a Form W-4 from 2020 or later with no entries in Steps 2 to 4. With those defaults, the method works out to applying the filing status’s 2026 rate schedule to annual wages minus the standard deduction, then dividing by the number of pay periods. As in Publication 15-T, married filing separately uses the single withholding table.
| 2026 figure | Value |
|---|---|
| Standard deduction | Single and married filing separately $16,100; married filing jointly $32,200; head of household $24,150 |
| Single brackets | 10% to $12,400; 12% to $50,400; 22% to $105,700; 24% to $201,775; 32% to $256,225; 35% to $640,600; 37% above |
| Married filing jointly brackets | 10% to $24,800; 12% to $100,800; 22% to $211,400; 24% to $403,550; 32% to $512,450; 35% to $768,700; 37% above |
| Head of household brackets | 10% to $17,700; 12% to $67,450; 22% to $105,700; 24% to $201,750; 32% to $256,200; 35% to $640,600; 37% above |
4. Social Security and Medicare
Social Security is 6.2% of wages up to $184,500 for the year. Medicare is 1.45% of all wages. Employers also withhold Additional Medicare Tax of 0.9% on wages above $200,000 in a year, regardless of filing status; the amount actually owed is settled on your tax return.
5. State Income Tax
State figures come from the Tax Foundation’s 2026 state income tax tables, which are compiled from state statutes and revenue departments. For each state we store the 2026 rate schedule (single and married filing jointly), standard deduction, personal exemption and personal credits.
The calculator estimates your yearly state income tax and spreads it evenly across your paychecks:
- State wages = gross pay minus pre-tax deductions the state allows. Pennsylvania and Massachusetts tax traditional 401(k) contributions; California and New Jersey tax HSA contributions.
- Taxable income = state wages minus the state’s standard deduction and personal exemption. Ohio’s exemption depends on income. Alabama also lets you deduct federal income tax.
- Tax = the state’s rates applied to taxable income, minus any personal credit, never below zero.
This is an estimate of tax owed, not the state’s official withholding table, so your pay stub can differ slightly. Head of household and married filing separately use the single schedule unless the state publishes separate brackets.
States shown as estimates
Some states have rules the calculator doesn’t fully model, and their results are labeled as estimates:
- Alabama: the married standard deduction phase-down isn’t modeled.
- Missouri: the partial deduction for federal tax isn’t applied.
- Ohio: the exact computation should be checked against the Ohio Department of Taxation.
- Oregon: the federal tax subtraction isn’t applied, so results are likely too high.
- Wisconsin: the standard deduction phase-down isn’t applied, so results may be too low.
States not yet modeled
Connecticut and Utah have income-based phase-outs that are still being verified, so the calculator leaves their income tax out and says so.
Local income taxes
Where cities, counties or school districts tax wages, the calculator offers a local tax box. Enter your local rate and it’s applied to your state wages.
State payroll taxes
Only contributions whose rate is fixed in state law are included: New York SDI (0.5%, up to $0.60 a week), Pennsylvania unemployment (0.07%), the Oregon statewide transit tax (0.1%), Connecticut Paid Leave (0.5% up to the Social Security wage base) and the WA Cares Fund (0.58%). Programs whose rates change each year, such as California SDI or paid family leave in several states, aren’t included yet, and the results say which ones are missing.
Social Security across the year
Per-paycheck Social Security and Additional Medicare amounts are yearly totals spread evenly. Real payroll stops Social Security once you reach $184,500 and starts Additional Medicare after $200,000, so high earners see uneven amounts on actual stubs.
6. Results
Net pay = gross pay − pre-tax deductions − federal income tax − Social Security − Medicare − state taxes − after-tax deductions. Effective tax rate = total taxes ÷ gross pay. Annual take-home = net pay × pay periods. Each line is rounded to the cent, as payroll systems do.
Limitations
- Withholding is not the same as tax owed. Credits, other income and itemized deductions are settled on your return.
- W-4 Step 2 (multiple jobs), Step 3 credits and Step 4 adjustments are not modeled.
- Bonuses and other supplemental pay may be withheld differently.
- Overtime is not calculated separately; include overtime hours in your hours per week at your blended pay.
- Employer-specific rounding and benefit rules can create small differences.
Testing
The calculator is checked against worked examples calculated by hand from the official formulas, for each filing status, before any change goes live.
See the full list of sources and references.