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 | Related Content Social Security Taxes Estimate how much of your Social Security benefit may be considered taxable. How to Appeal Your Property Taxes For homeowners who think their property taxes are too high, there are ways to appeal. Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one.