Precision Utility
Capital Gains Tax
Calculator
Tax Year
2025
NIIT Rate
3.8%
Calculate your 2025 US capital gains tax on investment profits. Enter your sale price, purchase price, holding period, filing status, and annual income to see your tax owed, NIIT liability, net proceeds, and effective rate.
Investment Details
Total Tax on Gains
$0
Capital Gain
$0
Tax Rate
0%
NIIT (3.8%)
$0
Net Proceeds
$0
Effective Rate
0.0%
How the capital gains tax calculator works
Enter your asset's sale price and original purchase price to determine your capital gain. Select your holding period (short-term or long-term), filing status, and annual income to calculate the tax you owe on your investment profit.
Short-term gains (assets held one year or less) are taxed as ordinary income at your federal tax bracket rate. Long-term gains (assets held more than one year) receive preferential rates of 0%, 15%, or 20% depending on your total taxable income.
The calculator also checks whether you are subject to the Net Investment Income Tax (NIIT), an additional 3.8% surtax on investment income for high earners. Your results show the total tax, NIIT amount, net proceeds after tax, and your effective tax rate on the gain.
2025 long-term capital gains tax rates
Long-term capital gains are taxed at three rates based on your taxable income (ordinary income plus capital gains):
| Rate | Single | Married Filing Jointly |
|---|---|---|
| 0% | Up to $48,350 | Up to $96,700 |
| 15% | $48,351 – $533,400 | $96,701 – $600,050 |
| 20% | Over $533,400 | Over $600,050 |
Additionally, the 3.8% NIIT applies when your modified adjusted gross income exceeds $200,000 (single) or $250,000 (MFJ). Source: IRS.gov.
Key strategies for reducing capital gains tax
Hold for more than one year. The simplest way to lower your capital gains tax is to hold investments for at least one year and one day to qualify for long-term rates, which are significantly lower than short-term rates.
Tax-loss harvesting. Sell losing investments to offset capital gains. You can deduct up to $3,000 in net losses against ordinary income per year, with unused losses carrying forward indefinitely.
Primary residence exclusion. If you sell your primary home and have lived in it for 2 of the past 5 years, you can exclude up to $250,000 (single) or $500,000 (MFJ) in gains from taxation.
1031 exchange. For investment real estate, a like-kind exchange allows you to defer capital gains tax by reinvesting the proceeds into a similar property within 180 days.
Short-term vs. long-term capital gains
The IRS draws a clear line at the one-year holding period. Assets sold within one year of purchase generate short-term capital gains, which are taxed at your ordinary income tax rate (10% to 37% for 2025).
Assets held for more than one year generate long-term capital gains, which benefit from lower preferential rates of 0%, 15%, or 20%. For most investors, this means a significant tax savings on patient, long-term investments.
This difference in rates is one of the most powerful incentives in the tax code for long-term investing and wealth building.
Frequently asked questions
What is the difference between short-term and long-term capital gains tax rates?
Short-term gains (assets held one year or less) are taxed as ordinary income at rates from 10% to 37%. Long-term gains (assets held more than one year) are taxed at preferential rates of 0%, 15%, or 20% depending on your income and filing status.
What is the wash sale rule?
The wash sale rule disallows a tax deduction for a loss on a security if you buy a substantially identical security within 30 days before or after the sale. The disallowed loss gets added to the cost basis of the replacement security.
What is tax-loss harvesting?
Tax-loss harvesting involves selling losing investments to offset taxable gains. You can offset unlimited gains with losses, and deduct up to $3,000 per year of net losses against ordinary income. Remaining losses carry forward to future years.
What is a 1031 exchange?
A 1031 (like-kind) exchange lets you defer capital gains tax on investment property by reinvesting proceeds into a similar property. You must identify the replacement within 45 days and close within 180 days. It applies only to real estate.
What is the primary residence capital gains exclusion?
If you sell your primary home and have lived in it for at least 2 of the past 5 years, you can exclude up to $250,000 of gains (single) or $500,000 (MFJ) from capital gains tax. This exclusion can be used once every two years.
What is the Net Investment Income Tax (NIIT)?
The NIIT is an additional 3.8% tax on investment income (including capital gains) that applies when your MAGI exceeds $200,000 (single) or $250,000 (married filing jointly). It is charged on top of your regular capital gains tax rate.