Regardless of genre, there is no hard and fast rule about how many pages or words each chapter should contain or how many chapters should be in a book. However, there are some general guidelines in this article that may help you determine the page count and chapter length needed for your book.
Pages in a Chapter:
Many people read in spurts, at lunch time, or on the subway to work, readers enjoy chapters that can be finished in ten to fifteen minutes.
I try to set my chapter lengths by how long it takes me to read the material. If it goes past fifteen minutes, I may decide to divide a chapter in half and make two chapters out of it. Take into consideration that I write mostly non-fiction.
As you probably know, there’s a difference in the way fiction and non-fiction are handled. In a fiction book, writers use shorter chapters. Some are only one page if that is all it takes to catch the reader up on the action of other characters in other scenes. When writing non-fiction, your chapter content needs to be specific to your chapter’s heading or title.
Twenty pages per chapter is a good rule of thumb, but the most important thing is to include everything that relates to a particular topic in one chapter. For example, if your book is about fishing, you want to include the bulk of your information about fly casting in one chapter. All your info about bait and lure would be in another chapter.
Chapters/Pages in a Book:
These guidelines should give you a general idea of how to determine the length of your chapters and your book.
If your book is titled “The Accuracy of the US Census” you may have 52 chapters (one on each state). If your book is titled “Ten Tips for Marketing” you may have only ten chapters. There’s no rule about how many chapters a book can or must have.
In order to be considered a book rather than a pamphlet or booklet, a book needs to be at least 10,000 words. If your book has more than 475 pages, you might want to consider producing it in two volumes.
Because you will submit your manuscript as an 8.5″ x 11″ word-processing document, you cannot be certain of its final length until after your publisher formats it for print. I have found that 250-300 words will approximate one page of 12-point font text in a standard size (5.5″x8″ or 6″x9″) perfect-bound book.