Book Output Topped Four Million in 2025

The total number of books published in the U.S. in 2025 with ISBN numbers jumped 32.5% over 2024, to more than four million books, according to statistics compiled by Bowker.

The increase was led by self-published works, for which the number of print and e-books (including those without BISAC codes) soared 38.7% to more than 3.5 million from 2.5 million in 2024.

The number of traditionally published books released in 2025 rose 6.6%, to 642,242, from 602,428 in 2024. That total includes 310,513 books that were released with BISAC codes, which are used to help classify the categories where books belong. There was a much smaller discrepancy among self-published books, suggesting that self-published authors have recognized the importance of using BISAC for discovery purposes.

Andrew Kovacs, product marketing manager for Bowker, offered a number of possible factors driving the rebound of self-published books in 2025, which had fallen in 2024 from 2023 levels. He posited that one reason for the increase is the growing availability and adoption of new tools in the author community.

“The fact that every aspect of the publishing process once available only through traditional publishers can now be obtained from the self-publishing service providers at a comparable level of quality” is likely the key driver in lifting output, Kovacs said.

These new tools, Kovacs continued, help authors not only write and publish books, but distribute and market them as well. And the ease to publish the same title in different formats—be it hardcover, paperback, or e-book (all of which require a unique ISBN)—is another reason for the increase in the number of books published, Kovacs said.

The most popular genres of self-published titles, the vast majority of which are published as e-books, remain generally consistent. In 2025, the top five genres were: fiction (477,104 books); juvenile nonfiction (401,716 books); games and activities (354,684 books); juvenile fiction (265,615 books); and travel (246,615 books).

These categories, along with self-help, accounted for over half of the increase in book output last year, Kovacs said.

On the traditional publishing side, adult fiction remained the most popular category, with 39,681 books published in 2025, followed by juvenile fiction, which had 24,768 books released last year. The figures in both categories were down slightly from 2024.

Rounding out the top five categories were juvenile nonfiction (21,283 books); business and economics (18,105 books); and religion (16,095 books).

Taking a longer-range view, the number of traditionally published books increased 10% between 2022 and 2025, while the number of self-published books jumped 43.5%.

Courtesy Bowker.