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 | Related Content Capital Gains Tax Estimator Use this calculator to estimate your capital gains tax. How Income Taxes Work A quick look at how federal income taxes work. Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one.