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 Retirement Plan Detectives A couple become Retirement Plan Detectives, searching records from old employers. Estimate Your RMD Help determine the required minimum distribution from an IRA or other qualified retirement plan. Once Upon a Goal Do you know how to set up your financial goals for success? This knight does.