So you’re writing a book with chapters, and you want to know how long the chapters should be. Cool. You’ve spent all day looking without success. Should have been simple to get an answer. But it wasn’t!
Why not?
The answer and the reason for the difficulty are related. The answer is “It depends”. And that wasn’t the answer you wanted. But don’t get discouraged, I’ll give you a more precise answer shortly.
But first, I need to explain why you’ve been having difficulty and why it depends is the answer.
First off you need to realize that what you are writing will affect the length of chapter you want to use. The more formal the book, the longer the chapters can be. A text book can have chapters as long as 20 or 30 standard double spaced pages. An executive how-to book should be around 10 pages. Fiction can have chapters as short as four or five pages. And even less.
Second, chapters are used to organize your book. Especially with executive or popular how-to books, the mind’s ability to process information is important. The length isn’t as important as the number of chapters. The cognitive limit suggests that we should have between 5 and 9 chapters. Chapter length will vary in order to work with that limit.
In fiction, the number of chapters is related to the story — the number of scene changes and time changes. Generally, a chapter or sub-chapter is used to underscore the change of scenery or time. This corresponds to the use of acts and scenes in a play. So one chapter could be 15 pages and another 2 pages.
The third issue has to do with a physical element of the market. How long does it take to read a chapter? When we read a fiction book especially, but also with executive or popular how-to books, readers use chapters to split up our reading. In other words, most people like to stop at a chapter end. That way they are picking up the book at a point the author has indicated is a stop. Most people can read 10 pages in a half-hour to an hour. Most people get to read in half-hour or hour blocks. So the market tends to favor books of 10 pages or so.
But just because most books have 10 pages per chapter doesn’t mean that your book should have 10 pages per chapter.
So you need to do some market research. Go to a bookstore and check some of the bestsellers in your niche. Or better still check some of the books accepted by your editor in your genre. Then count the number of pages in the chapters. Is there a lot of variation? Or are all chapters the same length? For one book are most chapters 10 pages long and another 15 on average? Or are they all the same length. Are they generally longer than 10 pages? The variation from book to book and within the book will give you an indication of how firm the requirement is for chapter length.
Once you know how open the market is to variation in chapter length, you’ll know if you need to stick to 10 pages per chapter, or 15 pages or if you have complete artistic control.