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 Message Thank you! Oops! Related Content Social Security Taxes Estimate how much of your Social Security benefit may be considered taxable. Five Most Overlooked Tax Deductions Five overlooked tax deductions to help manage your tax bill. Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one.