This amount may vary in places, but the total comission is usually 6% of the sale price of the house. There are also other variables involved. For example, let's say there is a listing agent (the real estate agent who listed the property), a selling agent (the real estate agent who sold the property) and the broker under whom both agents work.
In this case, the listing agent would get 2% of the total sale price, as would the selling agent and the broker. If the listing agent and selling agent are the same person, they would received 4% comission, and the broker 2% of the sales price. If the broker is also the listing and selling agent, then s/he gets the full 6% comission.