Buzz
When Johannes Gutenberg introduced the printing press in 1440, he could not have anticipated how his invention would eventually evolve into a worldwide industry producing millions of books annually. Over the centuries, the flow of new publications continues, while old books accumulate, leading to a number that would be unimaginable to someone who painstakingly set each letter by hand. Although attempting to tally all the physical books in bookstores, libraries, and private collections worldwide would be a monumental, if not impossible, task, we may be able to estimate the number of unique book titles ever published.
Determining the total number of books begins with a seemingly straightforward question: What exactly qualifies as a book? This question quickly veers into deep philosophical waters, and there is no single answer. In 2010, the Google Books team, which has set out to digitize every printed work, offering unprecedented access to global knowledge in one massive database, proposed their own definition. According to them, a “tome” is any “idealized bound volume,” ranging from a popular bestseller found at every airport kiosk to a rare, leather-bound edition no longer in print, to a solitary manuscript of an unpublished PhD dissertation sitting quietly in a university's archive.
This definition mirrors the concept behind International Standard Book Numbers (ISBN), the globally recognized identifiers for books sold in the commercial marketplace. However, ISBNs, which have only been around since the mid-1960s, are not universally adopted, especially outside the Western world, and relying on them alone leaves out significant portions of printed works. Moreover, even when ISBNs are used, the process for assigning them isn’t always thorough. As a result, many items that resemble books but are not, such as audiobooks, instructional DVDs, or flashcards, still receive ISBNs. Consequently, depending solely on ISBNs for the count of published books leads to an incomplete, unsatisfactory conclusion.
Other organizations have also tried to standardize their extensive book collections, such as WorldCat and the Library of Congress. However, these figures are often inflated because of differing cataloging rules that result in the same books being counted multiple times. Basic information like book titles, author names, and publishers can also be unreliable, as human error in data entry can lead to duplicate entries in databases.
Google Books has tackled this issue by considering these challenges, using them to cross-check nearly a billion raw records from 150 different sources. This allowed them to refine their data, eliminating duplicates and arriving at a more accurate count of unique books. After removing such redundancies, they also had to discard non-book entries, such as two million videos, two million maps, and a turkey probe that was humorously added as part of an April Fools' joke. In the end, Google Books tallied up—drumroll, please!—129,864,880 books in total. Phew.
But wait, there’s more! Despite Google’s diligent work, there are still critical gaps in their calculation: not only is their count outdated (it was last updated in 2010), but it also misses the surge in self-publishing, especially in digital formats. While ISBNs are recommended for all published works, they are not mandatory for self-published books, particularly those in e-book stores, and there is no effective tracking system for them. As self-publishing becomes more popular, with nearly half a million new titles released in 2013 alone, Google’s algorithm becomes increasingly disconnected from reality.
Until Google refreshes its methodology, we can attempt to estimate a more accurate total number of books published as of 2016. It’s a moving target, heavily reliant on inaccurate ISBNs, and will require some educated guesses, but here’s an attempt.
According to Bowker, the organization responsible for tracking all newly assigned ISBNs in the U.S., almost one million new titles were published between 2011 and 2013 (plus some reprints). A U.S. Industry and Trade Outlook statistic suggests that the United States produces roughly 40 percent of the world’s printed materials; if we assume the U.S. also accounts for a similar percentage of non-printed works, we can estimate the global book production during that period to be around 2,267,265 new books published worldwide from 2011 to 2013.
Finding recent data is challenging, so to estimate the book production between 2013 and today, we might average the number of new titles published in the last three years (755,755 annually worldwide) and add that to the 2013 figure. After doing some simple calculations, the estimated minimum number of unique books in existence by mid-2016 is (cue the drumroll) 134,021,533 total. And that’s the story—at least for now.
