This list is incomplete because there are many books, such as Alessandro Manzoni's Engaged, Alexandre Dumas' The Count of Monte Cristo, or Charles Dickens' A Christmas Carol, which are commonly referred to as "bestsellers", but they do not have reliable sales figures due to the many publicly available reprints.

According to the Guinness Book of World Records, the Bible is the best-selling book of all time— more than 5 billion copies of the book have been sold and distributed.
The Bible broke several records: its first was printed on the machine, it was translated into more than 2400 world languages.

The Quran is also one of the most widely circulated books around the world with more than a billion copies.
The Quran, like the Bible, and the Red Book are also translated into other languages, but due to social and cultural characteristics, the situation with the Koran is somewhat difficult, since not all translations are recognized by Muslims.

Many sources indicate that the "Quotes of Chairman Mao Zedong" (also often called the "Red Book" by Mao Zedong) were published in circulation. In addition, there appear to have been a large number of unofficial local reprints and unofficial translations of the book.

Accurate printing data for these and other books may be lacking or unreliable, as these books may have been produced by many different and independent publishers, in some cases over many centuries.
All of these books of a religious, ideological, philosophical, or political nature have been removed from this bestseller list for these reasons.

Comics and textbooks are also not included in this list.

With sales of over 500 million copies worldwide, J.K. Rowling's Harry Potter is the best-selling book series in history.

«Approximate Sales" in the table refers to the estimated number of copies of each book sold, not the number of books printed or currently in existence.