How we calculate

Method, sources and tax year notes, on one page.

The order of operations

Gross pay for the period is annualized by the number of pay periods: 52 weekly, 26 biweekly, 24 semi-monthly or 12 monthly. Section 125 health premiums come off first, because they reduce both income tax wages and FICA wages. A traditional 401(k) contribution comes off next for income tax only.

Federal income tax is then applied bracket by bracket to wages less the standard deduction. This matches IRS Publication 15-T's percentage method, whose standard schedules are algebraically the same calculation.

Social Security is 6.2% on the first $184,500 of FICA wages for 2026. Medicare is 1.45% with no cap, plus 0.9% above $200,000. Neither is reduced by a 401(k) contribution.

State tax is then applied using that state's own base. Most states start from the federal figure. Pennsylvania does not: it counts elective deferrals as compensation. Ohio municipalities add them back for local tax. Employee-paid programs such as California SDI, Washington Paid Family and Medical Leave and New Jersey TDI are applied on their own wage bases.

2026 federal figures

Federal figures come from IRS Rev. Proc. 2025-32, IRS Notice 2025-67, IRS Publication 15-T (2026) and the Social Security Administration's 2026 cost-of-living announcement.

What this does not cover

It estimates withholding and annual liability for wage income. It does not model itemized deductions, credits beyond the standard deduction, multiple jobs, self-employment income, equity compensation, or local taxes unless the state page says otherwise. Local rates in Indiana, Maryland, Ohio, Pennsylvania, Kentucky and Michigan are set by each jurisdiction and need checking against your own address.

These are estimates for planning, not tax advice. For a filing decision, speak to a qualified preparer.

State sources and confidence

Every state's figures, where they came from, and how confident we are. Where a state had not published a 2026 figure at the time of writing, we say so rather than guessing.