Goodreads Awards "Best selling" refers to the estimated number of copies sold of each book, rather than the number of books printed or currently owned.
Comics and textbooks are not included in this list.
The books are listed according to the highest sales estimate as reported in reliable, independent sources. This list is incomplete because there are many books, such as The Betrothed by Alessandro Manzoni, The Count of Monte Cristo by Alexandre Dumas, or A Christmas Carol by Charles Dickens, that are commonly cited as "best-selling books" yet have no reliable sales figures because of the many public domain re-releases. Similarly, many notable book series that sold very widely are poorly documented (Land of Oz, Freddy the Pig), consist of multiple sub-series (Tom Swift), or have lost sales due to being accused of promoting racist imagery (Dr. Dolittle).
According to Guinness World Records, the Bible is the best-selling book of all time, with over 5 billion copies sold and distributed. However, the Quotations from Chairman Mao Tse-tung, also known as the Little Red Book, has produced a wide array of sales and distribution figures — with some sources claiming over 6.5 billion printed volumes, others claiming the distribution ran into the "billions," and others citing "over a billion" official volumes between 1966 and 1969 alone as well as "untold numbers of unofficial local reprints and unofficial translations." The Qur'an is also widely reported to be one of the most printed and distributed books worldwide, with billions of copies believed to be in existence. Exact print figures for these and other books may also be missing or unreliable since these kinds of books may be produced by many different and unrelated publishers, in some cases over many centuries. All books of a religious, ideological, philosophical or political nature have been excluded from this list of best-selling books for these reasons.