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 Message Thank you! Oops! Related Content Surprises Making the most of surprises is a great reason to work with us. Tax Freedom Day Assess how many days you'll work to pay your federal tax liability. Important Birthdays Over 50 Here's a look at several birthdays and “half-birthdays” that have implications regarding your retirement income.