Which books have sold the most throughout history? The answer isn't as straightforward as it might seem. Older books that have been published for centuries have poor data, and a lack of copyright can allow for dozens of publishers to enter the field, making numbers even more difficult to count. Then there's the question of what counts as a single book—do you count The Lord of the Rings, for instance, as one item even though it was published as three separate books? (Tolkien himself clearly stated “The book is not of course a ‘trilogy’ . . . the story was conceived and written as a whole” and only split the story up because of length and cost issues.) Extending the issue, what is a book? Harry Potter and the Sorcerer's Stone has sold an estimated 120 million copies worldwide, but IKEA printed 203 million catalogs in 2017 alone, and both Sorcerer’s and IKEA are just over 300 pages in length.

With the understanding that the definition of a book is difficult; data is often impossible to confirm; that religious books like the Bible and Qur’an will be excluded; and that this list is not exhaustive, complete, or even a "top 10," these are candidates for some of the best-selling books in history.

  1. Quotations from Chairman Mao Zedong // Somewhere between 740 million and five billion copies sold

Mao Zedong
Mao Zedong
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Mao Zedong was the leader of China's Communist revolution, the leader of the Chinese Communist Party, and chief of state of the People’s Republic of China from 1949 to 1959. The scale of his Quotations, which includes 267 aphorisms on various aspects of life and politics, is difficult to fathom. According to Mao's Little Red Book: A Global History, between 1966 and 1970 printing Quotations used 650,000 tons of paper, around the same amount as all publications produced in China between 1949 and 1965. The book received plenty of government help: State banks gave distributors interest-free loans, production was exempt from tax, and transportation was free. Officially, 740 million copies were published between 1966 and 1968, and reportedly almost every citizen owned a copy.

  1. Xinhua Dictionary // 567 million copies sold

Considered by Guinness World Records as both “Most Popular Dictionary” and “Best-selling book (regularly updated),” the Xinhua Dictionary has been one of China’s best-selling books since 1953. Published by China's Commercial Press, it's the first dictionary (with pictures!) written in Mandarin Chinese, and is a widely used reference work in China in primary school and beyond.

  1. Harry Potter Series // 500 million copies sold across the entire series

Stacked Harry Potter books in black and white
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In 2018, it was announced that 500 million copies of the entire Harry Potter series had been sold. That's a long way from 1997, when the series started with a reported 500-copy first print run for Philosopher’s Stone (the British title). By 1999, when Prisoner of Azkaban came out, it sold 68,000 copies in the UK and immediately garnered controversy when the Sunday Times bestseller list refused to include it due to being a children’s book. By the time the series ended, Deathly Hallows managed to move 2.6 million copies in the UK and 8.3 million in the United States on a single day.

  1. The Lord of the Rings // Upwards of 100 million copies sold

Tolkien's fantasy books are, of course, some of the most beloved today. But in an interview with the Orlando Sentinel in 2003, Houghton Mifflin's Tolkien projects director Clay Harper discussed fears that the movie trilogy might bomb and dampen sales for a generation—so much so that Houghton Mifflin released new editions of the books to try to take advantage of the pre-release excitement before the first movie came out in 2001 (and to try and mitigate the potential disaster). After the movies, though, sales skyrocketed. Harper said that the company had, as of 2003, only two million-copy sellers: "One was Tolkien's The Silmarillion in 1977, and the other was The Lord of the Rings in 2001.”

  1. Le Petit Prince // Unclear, but a common estimate is 150 million copies sold

As with many of these numbers, actual data is difficult to come by—hence the likely undeservedly low place. But whether it’s near the top of the list or near the bottom, Antoine de Saint-Exupéry’s classic novella deserves its place because it’s thought to be the most translated non-religious work in the world. Guinness World Records reports it has been translated into 382 languages.

  1. And Then There Were None // Commonly estimated at 100 million copies sold

British mystery author Agatha Christie autographing French editions of her books
Author Agatha Christie autographing French editions of her books
Hulton Archive/Getty Images

And Then There Were None is generally considered the best-selling mystery novel of all time. Agatha Christie said that writing it required “a tremendous amount of planning” because of the sheer number of murders (10 people in total die, though not all are murdered). Christie later commented that the experience of adapting it for the stage is what “set [her] on the path of being a playwright as well as a writer of books.”

  1. The Da Vinci Code // Around 60 million copies sold

After Dan Brown's The Da Vinci Code was released, it spent a staggering 136 consecutive weeks on The New York Times best-seller list.

  1. Betty Crocker's Cookbook // Probably about 60 million copies sold

There is some disagreement about whether the best-selling cookbook of all time is from Betty Crocker or Better Homes and Gardens, but it’s generally given to Betty Crocker. "Betty" came into existence in 1921 after flour-makers the Washburn-Crosby Company began receiving an overwhelming number of baking questions in response to a contest they ran. The company decided they needed someone to sign off on the responses. They picked Betty as a nice, familiar name and Crocker in honor of retired director William G. Crocker. In 1924 “Betty” began a radio show, and even briefly appeared on television. Such was her fame that the first printing of her cookbook was 950,000 copies.

  1. The Poky Little Puppy // Around 15 million+ copies sold

In 2001, Publisher’s Weekly asked various publishing houses for statistics on their all-time bestselling children's books. Even though the main news was the success of Harry Potter novels (which had yet to have their huge explosion in popularity), the survey found that the most successful book on their ranking (and still considered the best-selling picture book of all time) was The Poky Little Puppy by Janette Sebring Lowrey, one of the most famous of the Little Golden Books. According to NPR, the goal of the Little Golden Books was to “democratize children’s books” by increasing their availability and lowering their price—in the process, making them iconic for generations of youngsters.

  1. Charlotte’s Web // 10 million copies sold in the United States

The same Publisher’s Weekly article found that the best-selling paperback children’s book of all time was Charlotte's Web. Beyond writing children’s books, E.B. White was a prolific essayist. One essay was "Death of a Pig," in which he detailed his efforts to save a sick pig. Sadly, the pig died, but the idea helped lead to his most popular children’s book.

Honorable Mention: Uncle Tom's Cabin // Probably circa 3 million copies sold

Three million hardly sounds impressive—Harry Potter and the Deathly Hallows sold almost three times that in just one day in just one country. But Uncle Tom's Cabin deserves its place on this list for its incredible success in its own day. An 1855 Edinburgh Review article estimated it sold more than a million copies in England, “probably ten times as many as have been sold of any other work, except the Bible and Prayer-book.” The article goes on to say that it’s been translated into Italian, Spanish, Danish, Swedish, Flemish, Polish, two different times in Dutch, and 12 different German translations. It is widely considered the most successful book of the 19th century.

Dishonorable Mention: A Tale of Two Cities // Nowhere near 200 million copies sold. Probably.

It seems that no list of best-selling books of all time (yes, those are all different links) can exclude A Tale of Two Cities and its supposed-200 million copies. But its inclusion may not be as warranted as its ubiquity would seem to merit. Writing in The Times Literary Supplement, writer and Oxford lecturer Peter Thonemann says that this claim appeared on Wikipedia from 2008 to early 2016. Then other writers and publishers, from the BBC to popular history writers, lifted the claim and republished it, to the point that it is now a well-attested piece of literary trivia. As to where the original number came from? Thonemann is unsure, but suspects “a hyperbolic 2005 press release for a Broadway musical adaptation of Dickens’s novel” that Thonemann dismisses as “pure fiction.” So keep writing; you might be just one press release away from the best-selling novel of all time, according to the internet.