When I started teaching people how to write their own nonfiction books, I was surprised by how many questions I received about book chapters—especially about chapter length.
“How long should a chapter be?”
“How many chapters do I need?”
“Should my chapters have sections?”
I was stumped as to why there were so many questions about chapters, and then an Author made it all clear:
“I’m just confused and looking for some rules to follow.”
Ahh yes. When we’re doing something new, it’s natural to want guidelines.
Here’s the problem: there are no “rules” for book chapters.
There are some standard ways of doing things and some conventions that most Authors follow. But for any “rule” you can find, I can show you exceptions that break it—and do it well.
That said, it’s worth laying out those standards, conventions, and averages, at least as a place to start.
In this blog post, I’ll answer the most common questions about chapters, and I’ll give you some basic guidelines to help you as you write your book.
How many chapters should a nonfiction book have?
Most nonfiction books have between 5 and 20 chapters.
Any less than 5 and your chapters may be running long or may contain too many ideas.
That said, there are plenty of books with 30 or 40 chapters. And some books, usually with very short chapters, can have 50+.
There’s no “right” answer to this question.
The standard conventions I’ll lay out in this post aren’t unbreakable rules written in stone. You should always make your own decisions about what works for your book.
If you’re looking for help structuring your book into parts and chapters, try this outline template as a starting point.
Does chapter size really matter?
Why does it matter how long your chapters are? It matters because of:
- what readers need
- what a chapter is
Understanding what a chapter is can really help when you’re deciding how to structure your book.
A chapter is one of the main ways to divide and separate your book into distinct ideas.
Generally speaking, a single chapter of a nonfiction book is:
- a single cohesive idea, and/or
- a step in the process you are describing, and/or
- a single argument or position
It can be one or all of those things.
So, the length of your chapters should be determined by the number of words it takes to present that idea, step, or argument fully, without over explaining it.
So, how long should a chapter be?
Rule 1. Short enough, and long enough
If chapters break your book into digestible ideas, the right chapter length comes down to how to present those ideas.
Readers need to grasp the content of your book so they can come away with a deep enough understanding to apply their new knowledge.
Readers also need to stay interested so they’ll read the whole thing.
Complex ideas might need longer chapters, but those run the risk of dragging and losing your reader’s attention.
Shorter chapters are easier to digest, but they run the risk of not giving the reader enough information.
Putting those together, here’s the first “rule” of chapter length. A chapter should be:
- Short enough to hold a reader’s interest
- Long enough to give that reader what they need
Rule 2. Shorter is better than longer
One mistake I see a lot of Authors make is trying to tell the reader everything there is to know about a subject.
But most readers aren’t reading your book out of general curiosity.
They’re reading your book to learn how to solve a problem.
Your readers want:
- all the information they need to solve that problem
- only what they need (and no more)
Authors tend to be great at the first part and lousy at the second. They offer a ton of extra information that might feel interesting to them but doesn’t help the reader.
Because of that natural tendency, err on the side of short chapters over long chapters. You’re far better off leaving your readers wanting more than you are boring them.
If they want more, they’ll find you. If you bore them, they’ll just walk away.
Rule 3. It’s good to be average
When it comes to chapter word count, it’s good to be average.
For one thing, being average meets readers’ expectations. If they thumb through your book and see chapters that fit their expectations, they’ll feel more comfortable about their ability to digest them.
Longer chapters, on the other hand, come with the possibility of turning readers off before they even buy the book.
If a reader starts looking through your book on Amazon and that next chapter feels like it never comes, or if the table of contents presents monstrous 40-page chapters, there’s a good chance they’ll feel intimidated by the content.
If you’d like some guidelines, you can assume that the average nonfiction book is about 50k words and that most nonfiction books have about 12 chapters.
So around 4,000 words would be an “average” chapter length.
That number actually lines up pretty well with the data we have on this. But again, that number should neither be a goal nor a constraint. It’s just a convention.
But it’s a convention that fits within your reader’s attention span.
One thing to remember about average chapter lengths is that they’re driven by:
- how much information most readers need to understand a good chapter topic
- the average attention span most readers have in absorbing a single idea
Rule 4. The Goldilocks limits
Chapters can be 500 words, or even 10,000. It all depends on how much you dive into an idea and how far you go with that idea.
That said, you never want your readers to think:
- “That chapter was too short,” or
- “That chapter was too long”
You want your chapters to be just right.
As a general rule, if a chapter is under 1,000 words, it might not be a whole idea or chapter. It might be part of something else. See if it makes more sense to combine it with another chapter.
If your chapter is more than 5,000 words, see if you can break it into different ideas. Maybe you can’t, and that’s okay. It’s just something to consider.
But if a chapter is more than 10,000 words, you should probably break it into two or more chapters.
Remember, books are structured in parts, chapters, and sections.
A part is simply a set of chapters that go together and fall under a larger idea.
So, if your chapter is more than 10K words, it might really be a part, not a chapter. See if you can break it into distinct ideas that would make good chapters.
Rule 5. Use chapter breaks wisely
Even the longest chapter in the world can be a page-turner if it’s structured and formatted well.
Chapter structure is about how you use sections to break up your chapter. A chapter might be a single idea, but each section should present a coherent piece of that idea.
If you break your chapters into small enough pieces, readers won’t have any trouble following them. In fact, they won’t even be intimidated if they flip through a long chapter ahead of time—as long as they see those breaks.
This is one of the ways Authors break the “rules” successfully.
Rule 6. Formatting makes a huge difference
Another way to make long chapters seem friendlier is to use smart formatting in your book.
Presenting material with charts, graphs, images, headings, bullet points, and other special formatting breaks up all that text and makes the content feel more manageable to the reader.
But it isn’t just about how to structure your content. It’s about the formatting itself.
Interior book designers use negative space (empty space) to make content feel more approachable.
When it comes to small, tightly-packed, unvarying text versus loose, flowing text with differentiated headings, the loose, flowing text will win out every time.
Your concepts are complex enough as it is. Don’t make your readers work harder by laying those concepts out in a way that’s difficult to take in. Readers won’t buy the book.
For one thing, they don’t want to work harder than they have to. But they also won’t have much faith in you as an Author if your book looks like you didn’t really put the work in.
The right interior layout invites the reader in and makes them feel welcome.
Rule 7. Your chapters don’t have to be the same length
In fact, having chapters of similar length doesn’t matter at all. If one chapter is 5,000 words, and the next 1,200, and then 3,000, and then 1,000, that’s completely fine.
It might even be beneficial. Varying the flow can make the book read better, depending on what you’re saying.
It’s far more important to worry about the flow of ideas for the reader than to worry about any of these chapter guidelines. Your book is written for your reader, so make chapter decisions based on what makes the best book for them.
Rule 8. There are no rules
When you’re staring at the first chapter of the first draft of your first book, it’s natural to look for writing advice with hard and fast rules.
Should you use 3,000 word chapters or 4,000 word chapters? Where should one chapter end and a new chapter begin?
But there’s no bestseller formula when it comes to chapter length. There just isn’t.
The only real rule is to make your chapters work for your readers.
If readers understand each chapter, connect the ideas, and flow easily from one to the next, that’s all that matters.
A book’s structure is never about confining the Author. It’s about serving the reader.
