Writing a book can be a daunting task, and many writers wonder how many words they need to complete a book. Is a 50,000 word manuscript long enough? Is a 200,000 word manuscript too long? (Another question is how many words make up a page in a printed book. That varies a lot, depending on the trim size and layout, but you might assume about 350 words per page.)

The simple (and best) answer to the question of how long your book should be is that you should write as many words as are needed to tell your story or share your information on the book’s subject, and no more. Reader expectations are important. They want books to be long enough to give them what they want, but not so long they get bored or feel overwhelmed. But you clicked on this article because you want a more specific answer, right? How can we figure out what readers expect and want?

One way to get an idea of what readers expect is to look at the length of similar books. Readers of fantasy novels may be accustomed to longer novels than romance readers are. On the non-fiction side, self-help books are usually not as long as historical books. If you are targeting a specific publisher with your work, read their guidelines to find out what their expectations are. They know what their readers are used to buying.

Looking at the bestsellers in your category will show you what books people are buying and if there is any correlation between length and sales. Recently, BookInABox.com did just that for the broad category of non-fiction. What they learned should probably not be a surprise.

BookInABox looked at all of the New York Times bestsellers from 2011 to 2017 and discovered that the average length of books on the list has dropped every year. In 2011, the average length of the #1 bestsellers was 467 pages. By 2017, that number had dropped to just 273 pages. And only 13% of the books atop the bestseller list contained 450 or more pages.

There are, of course, outliers. They point out that in 2016, Ron Chernow hit the #1 spot with his 816-page biography of Alexander Hamilton. However, in the period 2015 – 2017, more than 50% of #1 bestsellers were in the 250 – 350 page range.

So how long should your book be? Although there isn’t a one-size-fits-all answer, readers are clearly choosing to read shorter books than in the past. That is something to keep in mind as you edit your next masterpiece. Shorter doesn’t necessarily mean easier to write, though. This quote by Pascal (also attributed to Mark Twain and others) makes it clear that shorter is not always faster or easier: “I would have written a shorter letter, but I did not have the time.” To write a bestseller, write the best book you can. The length will likely influence sales, but it is not the only factor.