Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Have A Question About This Topic? Name Email Address Question Thank you! Oops! Related Content Understanding Marginal Income Tax Brackets An inside look at how marginal income tax brackets work. Working With A Financial Professional A financial professional is an invaluable resource to help you untangle the complexities of whatever life throws at you. Saving for College 101 Here’s a crash course on saving for college.