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 Separating the Signal From the Noise A good professional provides important guidance and insight through the years. Qualifying For Medicare Under Age 65 You might qualify for Medicare if you’re under 65-years-old. This article will explain the conditions where you may qualify for Medicare early. The Facts About Income Tax Millions faithfully file their 1040 forms each April. But some things about federal income taxes may surprise you.