Capital Gains Tax Calculator United States
Estimate US tax with this capital gains tax calculator. Compare long-term brackets for assets held over a year against short-term rates and see tax owed.
What it does
The US Capital Gains Tax Calculator estimates the tax on a capital gain, using long-term capital gains brackets for assets held over a year or your marginal rate for short-term gains.
Data sources & parameters
The figures below drive this calculator. We keep them aligned with the latest official guidance, and each result recalculates automatically whenever a value changes.
| Parameter | Value | Source | Last updated |
|---|---|---|---|
| LTCG 0%/15% and 15%/20% breakpoints, single | Rate schedule | irs.gov | Effective 2026-01-01 |
| LTCG breakpoints, married joint | Rate schedule | irs.gov | Effective 2026-01-01 |
| LTCG breakpoints, married separate | Rate schedule | irs.gov | Effective 2026-01-01 |
| LTCG breakpoints, head of household | Rate schedule | irs.gov | Effective 2026-01-01 |
| Long-term capital gains rate schedule (0%, 15%, 20%) | Rate schedule | irs.gov | Effective 2026-01-01Seeded from the IRC 1(h) rate schedule as published in IRS Topic no. 409; the 15% and 20% rates were previously hardcoded in capital-gains-us and tax-loss-harvesting-us. Values unchanged. |
We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.
The formula
Long-term: gain × LTCG rate for your income; short-term: gain × marginal rate
How it works
Long-term gains use the 0/15/20% brackets based on taxable income; short-term gains are taxed at your ordinary marginal rate. The tool applies the right treatment to the gain.
Where it is used
- Estimating capital gains tax before selling
- Comparing short-term vs long-term treatment
- Working out after-tax proceeds
Worked example
A $50,000.00 long-term gain for a single filer on $90,000.00 income is taxed … (an effective rate of …), leaving ….
What the capital gains tax calculator does
The US capital gains tax calculator estimates the tax you may owe when you sell an asset such as stocks, funds or property. It applies the long-term capital gains brackets for assets held longer than a year, or your ordinary marginal rate for short-term gains, and shows the estimated tax on your profit, so you can see before selling how much of the gain you keep.
How capital gains tax works in the US
A capital gain is the profit from selling an asset for more than its cost basis. The tax depends mostly on the holding period:
- Short-term gains apply to assets held one year or less and are taxed as ordinary income at your marginal rate.
- Long-term gains apply to assets held more than one year and qualify for preferential capital gains brackets, which are generally lower than ordinary income rates.
Selling just before or just after the one-year mark can change the rate applied to your entire gain. The holding period runs from the day after you acquire the asset to the day you sell it, so an asset held for exactly a year is still short-term, while one held for a year and a day is long-term. If you are close to the line, confirm the exact acquisition date before selling.
Short-term vs long-term: an example
Two investors have identical gains. One sells at eleven months and pays their ordinary marginal rate. The other waits past twelve months and pays the long-term rate, keeping noticeably more of the same profit. Toggle the holding period in the calculator to see the difference in estimated tax.
How to use the calculator
- Enter the sale price of the asset.
- Enter your cost basis, including purchase price and commissions.
- Indicate whether you held the asset more than one year.
- Provide your income so the correct rate can be applied.
The tool calculates your gain and estimates the tax using either the long-term brackets or your ordinary rate.
The role of cost basis
Your cost basis reduces your taxable gain. It generally includes:
- The purchase price of the asset
- Brokerage commissions and transaction fees
- Certain adjustments, such as reinvested dividends for funds
Investors who do not track reinvested dividends often overstate their gain and overpay. Records kept from the day you buy can lower the tax when you sell.
How income affects long-term rates
Long-term capital gains rates are tiered by taxable income, so as income rises, long-term gains can move into a higher capital gains bracket. The year you sell therefore matters: a large gain realized in a lower-income year may stay in a lower bracket, while the same gain in a high-income year can be taxed at a higher rate.
Someone between jobs, recently retired, or in a low-income early-career year may be able to realize long-term gains at a lower rate than in peak earning years. Spreading the sale of a large holding over more than one tax year can also keep the gain from landing in a higher bracket all at once. These choices depend on your full income picture.
Planning around capital gains
- Hold past one year where practical to get long-term rates.
- Offset gains with losses realized in the same year to reduce the net taxable amount.
- Choose the year of a large sale so the gain is not taxed at your highest possible rate.
- Track basis carefully so you never pay tax on money that was already your own investment.
These are general considerations, not personalized advice.
Reading your result
Treat the output as a planning estimate, not a filed calculation. The tool uses the current brackets and thresholds, but your real liability depends on your complete return, including other income, deductions and capital losses. Use it to compare scenarios, such as selling now at your ordinary rate versus waiting for long-term treatment, or how a different income level changes the bracket. For any significant transaction, confirm your position with the IRS or a qualified tax professional before acting.
This article is general information only and is not financial advice.
About This Capital Gains Tax Calculator
Use this capital gains tax calculator to get an instant, accurate estimate. The figures follow official IRS guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.
Tax year 2026
Frequently asked questions
How does the capital gains tax calculator work?
What is the difference between short-term and long-term gains?
What counts as the cost basis?
Do capital losses reduce my tax?
Does my income affect the long-term rate?
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