Capital Gain exclusion on Primary residence

As per IRC 121-
When you sell your primary residence, you can make up to $250,000 in profit if you're a single owner, twice that if you're married, and not owe any capital gains taxes if you meet the ownership and use tests. You will generally only need to report the sale of your home if your gain exceeds a certain dollar prescribed by law. You may be entitled to exclude gain from income if during the 5-year period ending on the date of the sale, you must have:

Owned the home for at least 2 years (the ownership test), and
Lived in the home as your main home for at least 2 years (the use test).
During the 2-year period ending on the date of the sale, you did not exclude gain from the sale of another home.

If you owned and lived in the property as your main home for less than 2 years, you may still be able to claim an exclusion in some cases (change in place of employment, health or unforseen circumstances)