It depends on whether it's your own residence or a rental. There are significant exemptions for the sale of your own home. Check the IRS and use the search.
For sales above $250,000 (single) or $500,000 (joint return), use Schedule D to report the sale and take credit for the exemption amount. Tax is paid on the excess.
The capital gains will be owed on the difference between what it was bought for and what it sold for. No capital gains are owed if the house is sold at a loss.
