Capital Gains Tax Estimator Use this calculator to estimate your capital gains tax. 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 Social Security Taxes Estimate how much of your Social Security benefit may be considered taxable. Six Most Overlooked Tax Deductions Six overlooked tax deductions to help manage your tax bill. Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates.