When I started teaching people how to write their own non-fiction books, I was surprised by how many people asked me questions about book chapters.

“What length should my chapters be?”
“How many chapters should go in my book?”
“Should I have parts and chapters?”

I was kinda 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 anxiety strikes, people just starve for certainty.

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.

In this blog post, I will answer the common questions about chapters and try to give you some basic guidelines to help you as you write your book.

What Is a Book Chapter?

Seems like a silly question, but it’s actually important to establish this for the rest of the piece.

A chapter is one of the main ways to divide and separate distinct ideas within a book. Modern non-fiction books always have chapters. This was not always the case. Many ancient works were not organized by chapter, and either were one long text like Beowolf, or were organized with verses, like Aristotle’s Politics.

A modern chapter is usually:

  • 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.

What Is the Difference Between a Part and a Chapter?

For books with lots of chapters, these are often grouped into several “parts,” as another subdivision of the book.

A part is simply a set of chapters that go together and fall under a larger idea. For example, from the Table of Contents of a book, there are three parts here, with a few chapters in each part.

Part 1Where to Start with Your Service Business
Chapter 1Entrepreneurship
Chapter 2Goals
Chapter 3Time Management (Are We There Yet?)

Part 2Taking Action in Your Service Business
Chapter 4Marketing Your Business
Chapter 5Building Community
Chapter 6Sales
Chapter 7Rejection

Part 3Advanced Service Business Techniques
Chapter 8Money Mindset/Money Matters
Chapter 9Support is Conditional

How Many Chapters Should Be in a Book?

Most non-fiction books have between 5 and 20 chapters.

Any less than 5 chapters, and your chapters may be running long or may contain too many ideas.

This being said, there are plenty of books with 30 or 40 chapters. And some books, usually with very short chapters, can have 50+.

There is not a “right” answer to this question. There is the standard convention above, but that is not some unbreakable rule, written in stone. You have to make your own decision about what works for your book.

How Long Should Chapters Be?

It depends on two factors: how much do you need to say, and what kind of tenor and rhythm do you want in your book?

Long chapters can be informative, but they can also drag or be too crammed with information and lose the reader’s attention.

You can fight that with short chapters that keep the reader’s attention and maintain a fast pace, but that can also be confusing to the reader.

If you’d like some guidelines, you can assume that the average non-fiction book is 50k words, and that they have 12 chapters, so around 4k 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.

Chapters can be 500 words, or even 10k. It all depends on how much you dive into an idea and how far you go with that idea.

Is There a Maximum or Minimum Length for a Chapter?

No. A chapter is a single argument, idea, or step in your process. That can be as long or as short as is necessary.

The only word of caution is to consider that if the chapter is under 1,000 words, it may not be a whole idea or chapter and may be part of something else.

And if it is more than 10k words, it may be two or more chapters.

Is It OK if Chapters are Different Lengths?

Of course it is. If one chapter is 5,000 words, and then 1,200, and then 3,000, and then 1,000, that is all fine.

In fact, it might be beneficial. Varying the flow can make the book read better, depending on what you are saying.

I will say this again: it’s far more important to worry about the flow of ideas for the reader than to worry about non-existent “rules” for chapters. Your book is written for your reader, so make chapter decisions based on what makes the best book for them.