Capital Gains Tax Calculator
Estimate the tax on your investment profits. Enter your purchase and sale prices, choose short- or long-term, and see the tax owed and your net profit.
US 2024 single filer: 0% under ~$47,025, 15% up to ~$518,900, 20% above. Check IRS.gov for your bracket and filing status.
Understanding the Capital Gains Tax Calculator
This tool estimates U.S. federal tax on capital gains: the profit from selling an asset such as a stock, fund, or property for more than you paid. It distinguishes short-term gains (assets held one year or less, taxed at ordinary income rates) from long-term gains (held more than a year, taxed at preferential 0%, 15%, or 20% rates). It helps investors gauge the tax cost of selling before they trade. Figures are educational estimates for U.S. federal tax only; state taxes, the 3.8% net investment income tax, and your full return can change the result. Consult a tax professional for filing.
How it works
Enter your purchase price (cost basis), sale price, holding period, filing status, and taxable income. The calculator finds the gain (sale minus basis), classifies it as short- or long-term by the holding period, and applies the matching rate. Short-term gains are added to ordinary income and taxed at your marginal bracket. Long-term gains use the 0/15/20% schedule keyed to income thresholds. For 2026, single filers pay 0% on long-term gains up to $49,450 of taxable income, 15% up to $533,400, and 20% above that. Read the output as an estimated federal tax owed on the gain.
Worked example
You buy stock for $10,000 and sell for $18,000 after 18 months, a $8,000 long-term gain. As a single filer with $60,000 of other taxable income, your gains fall in the 15% long-term bracket. Tax is 8,000 x 0.15 = $1,200. Had you sold at 11 months instead, the $8,000 would be a short-term gain taxed at your ordinary rate (say 22%), costing $1,760, roughly $560 more for selling too soon.
Tips & common mistakes
- Holding an asset just over one year can move a gain from ordinary rates to the lower long-term schedule.
- Long-term rates (0/15/20%) depend on total taxable income, not the gain alone.
- This estimate excludes state tax and the 3.8% net investment income tax, which can apply at higher incomes.
- Capital losses offset gains and up to $3,000 of ordinary income per year; carry the rest forward.
- Cost basis includes commissions and reinvested dividends; omitting them overstates your taxable gain.
Sources & methodology
- • Internal Revenue Service — Topic No. 409, Capital Gains and Losses (https://www.irs.gov/taxtopics/tc409)
- • IRS — 2026 inflation-adjusted capital gains thresholds, Rev. Proc. / Notice (https://www.irs.gov)
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Reviewed by the TopOpenTools editorial team · Last updated June 2026. These tools provide general estimates for educational purposes only and are not financial, tax, insurance, investment, or medical advice. Verify important decisions with a qualified professional.
Frequently Asked Questions
What is the difference between short and long-term gains?
In most countries (including the US), assets held longer than one year qualify for lower long-term capital gains rates, while assets held a year or less are taxed at your ordinary income rate.
What rate should I enter?
For US long-term gains, choose 0%, 15%, or 20% based on your income. For short-term gains, enter your marginal income tax rate. For other countries, enter your local capital gains rate.
Does this handle exemptions and allowances?
No — it is a simplified estimate. Real capital gains tax may include annual exemptions, primary-residence relief, surtaxes, and offsets for losses. Consult a tax professional.