0 / 15 / 20%
Long-term capital gains tax rates (2025)
37%
Maximum short-term gains rate (same as ordinary income)
3.8%
Net Investment Income Tax on high earners
>1 year
Holding period required for long-term treatment
Short-term vs. long-term capital gains
Assets held one year or less are short-term and taxed at your ordinary income marginal rate — up to 37% federally. Assets held more than one year are long-term and taxed at the preferential rates: 0% for income below ~$48,350 (single, 2025), 15% up to ~$533,400, and 20% above that. The difference between selling a stock at 11 months versus 13 months can be a tax rate swing of 10–17 percentage points.
Net Investment Income Tax (NIIT)
High earners face an additional 3.8% NIIT on top of capital gains rates. The NIIT applies to net investment income (including capital gains, dividends, and interest) for single filers with modified AGI above $200,000 or married filing jointly above $250,000. This pushes the effective long-term rate to 18.8% or 23.8% for top earners.
How to use the capital gains calculator
- Enter your total income (needed to place gains in the correct rate tier)
- Enter your capital gain amount and whether it's short-term or long-term
- Select your filing status
- Choose your state — many states tax capital gains as ordinary income
- Review the federal rate tier, NIIT applicability, state tax, and total tax owed
💡 Tax-loss harvesting
Capital losses offset capital gains dollar-for-dollar. If you have losing positions, consider selling them in the same tax year as a gain to reduce or eliminate taxable gains. You can then repurchase similar (not identical) investments after the 30-day wash sale window.
Common mistakes to avoid
- Selling just short of the one-year mark and paying short-term rates when waiting a few weeks would save significantly
- Ignoring the NIIT for high-income earners — it's 3.8% additional on top of the capital gains rate
- Assuming capital gains don't apply to collectibles, real estate, and crypto — they do
- Forgetting state capital gains tax — California taxes long-term gains as ordinary income (up to 13.3%)
- Not tracking your cost basis accurately, leading to over- or under-reporting of gains
Related calculators
The US Income Tax Calculator shows how adding capital gains affects your overall federal tax liability. If you're self-employed, the Self-Employment Tax Calculator handles a different type of non-wage income. And the Roth IRA vs. Traditional IRA Calculator shows how sheltering gains inside a retirement account changes the tax outcome permanently.