How many sales make a best selling book?

A book is generally considered a best-seller when it sells over 100,000 copies. However, this number can vary depending on the genre of the book and the specific market in which it is sold. For example, in the United States, a book must sell over 10,000 hardcover copies to be considered a best-seller on the New York Times Best Seller list. In the United Kingdom, a book must sell over 5,000 copies in its first week of release to be considered a best-seller on the Sunday Times Bestseller list.