Capital Gains Tax Calculators

This planning estimate subtracts purchase basis and entered positive basis adjustments from sale proceeds, floors losses at $0, and classifies 13+ entered whole months as long-term because IRS rules require more than one year. General long-term gain is stacked over other federal taxable income through the official 2026 0%/15%/20% brackets; short-term gain is the incremental tax through the official 2026 ordinary brackets for the selected filing status. Incremental NIIT is 3.8% of the lesser-of calculation using entered MAGI and net investment income before and after the gain.

Federal regular tax uses official 2026 IRS ordinary and long-term brackets, but assumes the entered transaction is a net gain eligible for the general rates and omits collectibles, unrecaptured section 1250 gain, section 1202 stock, home-sale exclusions, transaction costs, other gains/losses, and AMT. NIIT uses the entered MAGI and net-investment-income proxies. The calculators do not prepare Schedule D, Form 8949 or Form 8960.

State tax is the modeled gain multiplied by the editable Modeled State Rate on each state page. It is not a state return calculation; a state page with its own rule table shows where that state's actual rule differs.