What Is an Income Tax Calculator?

This free federal income tax calculator estimates your 2024 US federal income tax liability based on your gross income and filing status. It uses the official 2024 IRS tax brackets to show your marginal rate, effective rate, and estimated after-tax income.

How to Use This Calculator

Enter your annual gross income (before taxes).
Select your filing status.
Optionally enter any additional deductions above the standard deduction.
Click Calculate Tax to see your estimated tax and effective rate.

2024 Standard Deductions

Single: $14,600
Married Filing Jointly: $29,200
Head of Household: $21,900
Married Filing Separately: $14,600

This calculator estimates federal income tax only. State income taxes and FICA (Social Security/Medicare) are not included. Consult a tax professional for a complete picture.

How Is Federal Income Tax Estimated?

Tax = Σ (taxable_income_in_bracket × bracket_rate)

Variable Definitions

Taxable Income

Gross income minus standard deduction and other deductions

Brackets

2024 federal marginal tax brackets (10%, 12%, 22%, 24%, 32%, 35%, 37%)

Effective Rate

Total tax ÷ gross income × 100%

💡 Federal income tax in the US is progressive — only income within each bracket is taxed at that bracket's rate. This calculator uses 2024 tax year brackets. State income taxes are not included.

Frequently Asked Questions — Tax Calculator

What is the standard deduction for 2024?

For 2024, the standard deduction is $14,600 for single filers, $29,200 for married filing jointly, and $21,900 for heads of household. If your itemized deductions (mortgage interest, charitable giving, state/local taxes, etc.) exceed the standard deduction, it may benefit you to itemize.

What is the difference between marginal and effective tax rate?

Your marginal rate is the rate applied to your last dollar of income — the highest bracket you fall into. Your effective rate is your total tax divided by your total income — your true overall tax burden. Because the US tax system is progressive, your effective rate will always be lower than your marginal rate.

Income Tax Calculator