US Federal Tax Calculator

Use this calculator to estimate US federal income tax from taxable income.

What this calculator does

The US federal tax calculator estimates federal income tax before credits, state tax, payroll tax, and local tax.

It uses:

• filing status
• taxable income
• standard deduction or estimated deductions
• federal tax brackets

This gives you an estimated federal income tax amount and an effective tax rate to use for planning.

US Federal Tax Formula

Federal Tax = Taxable Income Applied Across Progressive Brackets

Where:

• Taxable income = income after deductions
• Marginal tax rate = the rate applied to the next dollar of income
• Effective tax rate = total federal tax divided by income

Example calculation

If taxable income after deductions is 80,000 for a single filer, the calculator applies each part of that income to the relevant federal bracket rather than taxing the full amount at one rate.

That means only the income inside the highest bracket reached is taxed at the marginal rate. The effective rate is usually lower than the top bracket shown.

When to use this calculator

Use this calculator when you want to:

• estimate federal income tax for budgeting or withholding checks
• compare tax impact across filing statuses
• understand marginal vs effective tax rate
• plan quarterly estimated payments alongside other taxes

For bracket-specific detail, use the Income Tax Bracket Calculator.

FAQs

Is federal income tax the same as payroll tax?

No. Federal income tax is calculated from taxable income and tax brackets. Payroll tax funds Social Security and Medicare and is calculated separately.

Why is my effective tax rate lower than my tax bracket?

Federal tax brackets are progressive. Only the income inside each bracket is taxed at that bracket's rate, so your total effective rate is usually lower than your highest marginal rate.