Capital Gains Tax Calculator

Estimate your capital gains tax on investments, real estate, or other assets. Covers both short-term and long-term rates based on your income and filing status.

This calculator computes the tax on the gain between what you paid for an asset (Purchase Price) and what you sold it for (Sale Price), applying different rate logic depending on Holding Period. Sale Price is the single biggest driver of Capital Gain, since Gain = Sale Price - Purchase Price and Sale Price moves it in a straight 1:1 line, outweighing Purchase Price's equal-but-opposite pull because the default sale price is larger. Holding Period and Filing Status never move Capital Gain itself -- it's pure arithmetic on the two prices -- but they fully determine Tax Rate: short-term gains (held under a year) are taxed as ordinary income at your current-year marginal rate via marginalFederalRate, while long-term gains use the 2026 preferential brackets in CAPITAL_GAINS_2026 (0%, 15%, or 20% by income and filing status). Filing Status is the bigger lever on Tax Rate at the default $75,000 income: married filing jointly's 0% long-term bracket runs all the way to $99,400, well above that income, while single's 0% bracket tops out at $49,700, so the same income and gain can owe 15% as a single filer and 0% as a married joint filer. Because Tax Owed is Capital Gain multiplied by Tax Rate, a filing-status swap that zeroes out the rate can swing Tax Owed by more than a price change does for long-term gains at this income -- though for short-term gains, where the rate tracks ordinary brackets more gradually, Sale Price is the more consistent driver. Sale Price dominates Net Proceeds in either case, since Net Proceeds is Sale Price minus Tax Owed and the sale price term is larger. This model doesn't account for the Net Investment Income Tax, state capital gains tax, wash sale rules, or cost basis adjustments like depreciation recapture on real estate.