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 The Pre-Retirement Checklist This checklist can give you a quick snapshot of how prepared you are. When Do You Need a Will? When do you need a will? The answer is easy: Right Now. Estate Management 101 A will may be only one of the documents you need—and one factor to consider—when it comes to managing your estate.