Capital Gains Tax Calculator

Selling stock, a second property, or your home? The tax depends on three things most calculators blur: how long you held it, what your basis is, and how gains and losses net against each other. This calculator handles short-term and long-term lots separately, applies the netting rules in the correct order, uses the statutory §121 home-sale exclusion, and shows every step. No signup, no estimate inflation, constants cited with verification status, and a snapshot URL that replays your exact calculation.

General investments. Stocks, funds, crypto, and other assets. Enter purchase price, sale price, and costs.

Home sale (§121). Your primary residence. The statutory exclusion is $250,000 of gain for single filers and $500,000 for married filing jointly, if you owned and lived in the home long enough to qualify. Be careful with tools that show outdated exemption amounts — some calculators still use figures below the statutory values, which overstates your tax. We lock the legal numbers in code and cite the source.

Rental property. Basis is reduced by depreciation you claimed (or could have claimed), which is taxed at recapture rates on sale. The calculator flags this as a simplification point — rental sales frequently deserve professional review.

State add-on. Append a state estimate (California and New Jersey have notable capital-gains interactions) in the combined view, or run the full state calculator for the 10 supported states.

Purchase price and acquisition costs. Your basis starts at what you paid, plus fees and commissions.

Sale price and selling costs. Net proceeds set the gain ceiling.

Holding period. Enter dates or toggle short/long. Holdings of one year or less are short-term; more than a year is long-term. The boundary is applied automatically (greater than 365 days).

Short-term gains and losses. Each ST lot nets against other ST lots first.

Long-term gains and losses. LT lots net internally first — the order matters.

Prior-year loss carryforward. Losses beyond the annual cap roll forward; enter your carryforward so the netting is complete.

Filing status and ordinary income. The long-term rate depends on where your taxable income falls relative to the LTCG breakpoints.

1. Basis = purchase price + acquisition costs; gain = net sale price − basis.
2. Net short-term = sum of ST gains and losses; net long-term = sum of LT gains and losses (each internally first).
3. Net the two nets against each other: an overall loss is deductible against ordinary income up to $3,000 per year, with the remainder carried forward.
4. Net long-term gain is taxed at the LTCG rates. For 2026, the breakpoints are: 0% up to $49,450 (single) / $98,900 (married filing jointly); 15% up to $545,500 / $613,700; 20% above. Short-term net gains stack onto ordinary income at regular bracket rates.
5. The §121 exclusion applies before netting when the home-sale scenario qualifies.
6. Qualified dividends note: a dividend counts as long-term (qualified) only if you held the stock more than 60 days around the ex-dividend date — otherwise it lands in ordinary income. The calculation itself runs on the qualified dividends and capital gains tax worksheet, not merely by adding Schedule D lines.

Worked example (engine-computed at build time): [ENGINE-EXAMPLE:scenario=home_sale,filing_status=married_jointly,basis=400000,sale_price=900000,owned_years=6,used_years=6]

• §121 exclusion: $250,000 single / $500,000 MFJ (statutory; locked by test).
• 2026 LTCG breakpoints: 49,450 / 98,900 / 545,500 / 613,700 — pending IRS first-hand verification.
• Annual capital loss cap: $3,000, remainder carried forward indefinitely.
• Sources: IRC §121; IRS Publication 523 (selling your home); Schedule D and Form 1040 instructions.

This calculator produces an estimate for planning purposes. It is not tax advice, and it is not a substitute for filing an accurate return. Rental, trust, and estate situations are fact-specific — consult a professional.

Frequently asked