Amazon said Monday that sales of electronic books for its Kindle e-book reader have surpassed sales of hardcover books on the site.
"Even while our hardcover sales continue to grow, the Kindle format has now overtaken the hardcover format," Jeff Bezos, founder and chief executive of Amazon.com, said in a statement. "Amazon.com customers now purchase more Kindle books than hardcover books."
Bezos said this was "astonishing" given that the site has sold e-books for just 33 months, compared to 15 years with hardcover books.
Specifically, for every 100 hardcover books sold by Amazon, the company now sells 180 Kindle books – up from 143 for the past three months. Amazon has sold three times as many Kindle books in the first half of 2010 than it did in the first half of 2009.
The Kindle bookstore now has 630,000 books, including 106 of the 110 New York Times best sellers. About 510,000 of these books are $9.99 or less, Amazon said, while 1.8 million are free, out-of-copyright books.
Five authors - Charlaine Harris, Stieg Larsson, Stephenie Meyer, James Patterson, and Nora Roberts – have sold more than 500,000 Kindle books.
The news comes almost a month after Amazon dropped the price of the Kindle from $259 to $189 – hours after competitor Barnes & Noble slashed the price of its Nook e-reader to $199. Days later, Amazon also cut the price of the larger Kindle DX from $489 to $379.
Bezos said sales of the Kindle have tripled since Amazon lowered its price.
Amazon is expected to announce its second quarter financial results on Thursday.