It is the first thing people ask, and almost nobody has been given a number. Usually it is far smaller than they fear, because the law already shelters a large piece of it and most owners have never counted their improvements. This works out what is actually left.
Free. No sign-up. Nothing is saved or sent.
Ask this first because it is the biggest lever on the page. A couple filing jointly shelters $500,000 of gain. A single filer shelters $250,000. Nothing else you enter moves the answer this much.
A rough figure is fine. You can change it.
The original purchase price, not what it is worth now.
This is the one only you know, and it is the one that moves the answer most. A roof, an addition, a kitchen, a pool, windows, HVAC. Repairs and painting do not count.
The gain from the sale stacks on top of this in the year you sell, which is what pushes people into a higher bracket. A rough figure is fine.
Estimated capital gains tax
$0
Type your numbers and the sheet fills in.
What the sale brings in
Your gain
What you would owe
Why it is smaller than you think
Most people underestimate what they have put into a house over twenty or thirty years, and every dollar of it lowers the gain that gets taxed. Old permits, contractor invoices and credit card records all count as proof. If you can find them, the number above changes in your favor. Here is what people open next.
Plain answers on how the home sale exclusion works. General information about public tax rules, not advice about your situation.
You start with the sale price, subtract what it cost to sell, then subtract your adjusted basis. Adjusted basis is what you paid for the house plus every capital improvement you made over the years. What is left is the gain. The exclusion comes off that gain, and whatever remains is taxable. The number that surprises people is not the sale price. It is how much the improvements change the answer.
It is the part of a home sale gain the IRS does not tax. A single filer excludes $250,000. A married couple filing jointly excludes $500,000. Those two amounts were set in 1997 and have never been raised for inflation, which is why a house bought around then can produce a taxable gain even though the shelter sounded generous at the time.
Three tests. You must have owned the home at least two of the last five years. You must have lived in it as your main home at least two of the last five years, and those two years do not have to be back to back. And you must not have used the exclusion on another home in the previous two years. Anyone who has lived in their home for many years clears the first two tests without having to think about them.
Improvements raise your basis. Repairs do not. A new roof, an addition, a kitchen remodel, a pool, new windows, a new HVAC system are improvements. Painting, fixing a leak and replacing a broken window are repairs. Over twenty or thirty years the improvements add up to real money, and every dollar of them lowers the gain the IRS can tax. Keep the receipts you still have.
When someone inherits a home, their basis resets to the market value on the day they inherit it. The gain that built up over a lifetime is not taxed. That is a real financial reason some owners choose to stay, and it deserves an honest answer rather than a sales pitch. Whether it is right for you depends on your own plans, and a CPA and an estate attorney are the people to ask.
No. It is an illustration built from the numbers you typed, using a blended estimate of federal, state and Net Investment Income tax. Your real rate depends on your total income, your filing status and details this page does not ask for. Use it to see the shape of the problem and roughly how big it is, then take it to a CPA who can give you the real figure.
Sources: IRS Publication 523, Selling Your Home, and Internal Revenue Code Section 121. Checked August 2026. Rates and thresholds change, so confirm anything here with a tax professional before you act on it.
We will pull the real numbers for your address, put the improvements you can document against them, and send back a one page sheet. It is free and it stays yours whether we ever speak again.
Get it for my address