Amazon said it sold "well over" one million Kindle devices per week in December with the Kindle Touch and basic Kindle taking the top two spots after the Fire.
Amazon said the Kindle is its best-selling item in Britain, France, Germany, Italy and Spain in addition to the United States.
The company said "gifting" of Kindle books between November 25 and Christmas Day rose 175 percent compared to the holiday period last year with Christmas Day the biggest day ever for Kindle book downloads.
2011 was also a record-breaking holiday season for businesses that sell on Amazon. Third-party sellers experienced record holiday growth: the number of sellers who exceeded $5,000 in sales during the holiday season increased 44 percent year-over-year. For the year, businesses on Amazon sold hundreds of millions of units worth billions of dollars worldwide.
The Kindle Fire costs $199, less than half the price of the cheapest iPad from tablet market leader Apple.
Kindle Fire has a seven-inch (17.78-centimeter) screen, smaller than the iPad's 9.7 inches, connects to the Web using Wi-Fi and is powered by Google's Android software. It does not have a camera or the 3G connectivity featured on other tablets but it gives buyers easy access to Amazon's online store, which sells books, music, movies, television shows, games and other content.