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 Making Your Tax Bracket Work Have you explored all your options when it comes to managing your taxable income? What If You Get Audited? The chances of an IRS audit aren't that high. And being audited does not necessarily imply that the IRS suspects wrongdoing. Tax Freedom Day Assess how many days you'll work to pay your federal tax liability.