Complete guide: US Income Tax (Federal + State)
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Your US take-home pay depends on three layers of tax: federal income tax, your state's tax and FICA (Social Security and Medicare). The federal tax is progressive: your taxable income is split into brackets taxed from 10% to 37%. That is why your marginal rate (on your last dollar) is always higher than your effective rate (the real average you pay).
Before brackets apply, a deduction is subtracted: the standard one for your filing status, or your itemized deductions if they are higher (mortgage, donations, state taxes). Each qualifying child also reduces your federal tax through the child tax credit. FICA is separate: 6.2% for Social Security up to the wage cap and 1.45% for Medicare, plus 0.9% extra on high incomes.
State tax varies widely: nine states such as Texas, Florida or Washington charge no income tax, while California or New York exceed 8%. This calculator estimates state tax with a representative rate per state; for an exact figure check your state's official tables. Use it to compare job offers across states, plan your budget or estimate your refund.
How it works
- 1We subtract your deduction (standard or itemized, whichever is higher) from your gross income.
- 2We apply the 2025 federal brackets (10% to 37%) and subtract the child tax credit.
- 3We add the estimated state tax and FICA (Social Security + Medicare).
- 4We show your annual and monthly net, effective and marginal rates, and the bracket breakdown.
Frequently asked questions
What are the effective and marginal rates?
The effective rate is total tax divided by gross income: what you pay on average. The marginal rate is your top bracket: what you would pay on one additional dollar.
What is FICA?
It is the Social Security contribution (6.2% up to the wage cap) and Medicare (1.45%, plus 0.9% extra on high incomes). It is withheld from your paycheck on top of income tax.
Which states have no income tax?
Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington and Wyoming levy no state tax on wages.
Standard or itemized deduction?
Itemize only if your deductible expenses (mortgage, donations, state taxes) exceed the standard deduction for your status. The calculator automatically takes the larger one.
How accurate is the state estimate?
We use a representative rate per state on federal taxable income. States have their own brackets and deductions, so the real figure may vary.