Social Security Taxes Estimate how much of your Social Security benefit may be considered taxable. You are viewing this website at a small screen resolution which doesn't support calculators. Click here to view this calculator. Share | Have A Question About This Topic? Name Email Address Question Thank you! Oops! Related Contents The Facts About Income Tax Millions faithfully file their 1040 forms each April. But some things about federal income taxes may surprise you. Understanding Marginal Income Tax Brackets An inside look at how marginal income tax brackets work. Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates.