Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total capital gains tax
$6,375
Taxable gain
$42,500
Federal tax
$6,375
State tax
$0
Net proceeds after tax
$78,125
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter sale price ($).
- 2Enter cost basis ($).
- 3Enter selling costs ($).
- 4Enter holding period.
- 5Enter long-term rate (%).
- 6Enter ordinary income rate (%).
- 7Enter state tax rate (%).
- 8Read your total capital gains tax on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Assets held over a year qualify for long-term capital gains rates of 0%, 15%, or 20% federally, which are far kinder than short-term rates that follow ordinary income. Holding period is often worth more than timing the market.
Worked example
Using the values the calculator loads with:
Inputs
- Sale price: 85000 $
- Cost basis: 42000 $
- Selling costs: 500 $
- Holding period: Long-term (over 1 year)
- Long-term rate: 15 %
- Ordinary income rate: 24 %
- State tax rate: 0 %
Results
- Total capital gains tax: $6,375.00
- Taxable gain: $42,500.00
- Federal tax: $6,375.00
- State tax: $0.00
- Net proceeds after tax: $78,125.00
What each field means
Inputs
- Sale price ($)
- The sale price used in the calculation, measured in $. Starts at 85000 $ so you have a working example on load.
- Cost basis ($)
- The cost basis used in the calculation, measured in $. Starts at 42000 $ so you have a working example on load.
- Selling costs ($)
- The selling costs used in the calculation, measured in $. Starts at 500 $ so you have a working example on load.
- Holding period
- Pick the option that matches your situation — the maths changes per option. Choices: Long-term (over 1 year), Short-term (1 year or less).
- Long-term rate (%)
- The long-term rate used in the calculation, measured in %. Starts at 15 % so you have a working example on load. Accepted range: 0–30 %.
- Ordinary income rate (%)
- The ordinary income rate used in the calculation, measured in %. Starts at 24 % so you have a working example on load. Accepted range: 0–50 %.
- State tax rate (%)
- The state tax rate used in the calculation, measured in %. Starts at 0 % so you have a working example on load. Accepted range: 0–15 %.
Results
- Total capital gains tax
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Taxable gain
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Federal tax
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- State tax
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net proceeds after tax
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the capital gains tax calculator work?
Assets held over a year qualify for long-term capital gains rates of 0%, 15%, or 20% federally, which are far kinder than short-term rates that follow ordinary income. Holding period is often worth more than timing the market. The underlying maths is: Gain = Sale proceeds − Cost basis − Selling costs. Tax = Gain × applicable rate.
What do I need to enter?
7 values: sale price, cost basis, selling costs, holding period, long-term rate, ordinary income rate, and state tax rate. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the total capital gains tax result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Capital Gains Tax Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/capital-gains
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/capital-gains" target="_blank" rel="noopener">Capital Gains Tax Calculator — RevenueLab</a> (2026).</p>
Source: [Capital Gains Tax Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/capital-gains) (2026).