Example Data Table
| Scenario |
Sale Price |
Basis |
Expenses |
Other Income |
Holding |
| Stock Sale |
$150,000 |
$95,000 |
$2,500 |
$85,000 |
Long Term |
| Short Trade |
$40,000 |
$33,500 |
$250 |
$70,000 |
Short Term |
| Collectible |
$25,000 |
$10,000 |
$500 |
$110,000 |
Long Term |
Formula Used
Amount realized = gross sale price minus selling expenses.
Adjusted basis = original cost plus basis additions minus basis reductions.
Current gain or loss = amount realized minus adjusted basis.
Short term tax = ordinary tax after short gain minus ordinary tax before short gain.
Regular long term tax stacks long term gain above other taxable income. It applies 0%, 15%, and 20% bracket ranges.
NIIT = 3.8% of the lesser of net investment income or MAGI over the filing threshold.
Total estimated tax = federal capital tax impact plus NIIT plus estimated state tax.
How to Use This Calculator
Choose the tax year and filing status first.
Enter taxable income before capital gains.
Add the sale price, selling expenses, cost basis, additions, and reductions.
Select the holding period, or use dates for automatic testing.
Add carryover losses and other gains when needed.
Use collectible and section 1250 fields only when they apply.
Enter MAGI and select NIIT if higher income rules may apply.
Press Calculate. The result appears above the form.
IRS Capital Gains Planning Guide
A capital gain starts with a simple sale. You compare the amount realized with adjusted basis. The amount realized usually means sale proceeds minus selling costs. Adjusted basis can include purchase cost, improvements, reinvested expenses, and other allowed adjustments. The difference becomes gain or loss.
Why Holding Period Matters
Holding period drives the tax path. Assets held one year or less usually create short term gain. That gain is added to ordinary taxable income. Assets held more than one year usually create long term gain. Long term gain receives preferred federal brackets. The calculator separates these results so the estimate stays clearer.
Income Stacking
Long term gain is not taxed alone. It stacks on top of other taxable income. First, the tool places ordinary taxable income in the federal schedule. Then it moves qualified long term gain through the zero, fifteen, and twenty percent ranges. This gives a closer estimate than applying one flat rate to all gain.
Advanced Inputs
Investment sales can include fees, prior losses, collectibles, real estate depreciation, and state tax. This page includes those fields for planning. Collectibles can face a higher maximum rate. Unrecaptured section 1250 gain can also use a special maximum rate. Net investment income tax may apply for higher income taxpayers.
Using Results Carefully
The output shows proceeds, basis, net gain, federal tax, state estimate, NIIT, total tax, and after tax proceeds. It also shows effective rate and blended rate. Download the CSV for spreadsheets. Download the PDF for client notes or personal records.
Important Limits
This calculator is an educational estimator. It cannot replace Form 8949, Schedule D, or personalized advice. Wash sales, home sale exclusions, installment sales, partnership items, options, inherited assets, and business sales can change the answer. Keep records. Review your entries. Ask a qualified tax professional before making large transactions.
Planning Ideas
Many users test several sale prices before choosing an action. You can also compare selling this year with waiting. A smaller sale may keep more gain inside a lower long term bracket. A harvested loss may offset gain. A higher ordinary income year may raise the final tax cost. These checks support better timing, cleaner records, and calmer decisions later.
FAQs
1. What is a capital gain?
A capital gain is the profit from selling a capital asset. It is generally the sale amount minus selling costs and adjusted basis.
2. What is adjusted basis?
Adjusted basis usually starts with purchase cost. It may change for improvements, depreciation, fees, reinvestments, gifts, inheritance, or other tax adjustments.
3. What makes a gain short term?
A gain is usually short term when the asset was held one year or less. Short term gains are usually taxed as ordinary income.
4. What makes a gain long term?
A gain is usually long term when the asset was held more than one year. Long term gains may use 0%, 15%, or 20% federal rates.
5. Does this calculator include NIIT?
Yes. Select NIIT and enter MAGI. The tool estimates the 3.8% tax using the lesser-of rule and filing threshold.
6. Can I include capital losses?
Yes. Enter other gains or losses, plus short term and long term carryover losses. The tool offsets gain categories for planning.
7. Are collectibles handled?
Yes. Enter the collectible portion separately. The calculator estimates that portion using the maximum 28% federal rate.
8. Is this a final tax filing result?
No. It is an estimator. Tax forms, elections, exceptions, state rules, and professional advice may change your final tax result.