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? Address Thank you! Oops! Related Contents Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one. “Dirty Dozen” Tax Scams to Watch For Every year the IRS releases its list of tax scams, spotlighting some ways that people try to separate you from your money. Federal Income Tax Use this calculator to estimate your income tax liability along with average and marginal tax rates.