I was asked the question, the other day. “How big (word count) should chapters be?” and this implied “How big (word count) should the story be?” Also implied would be, “How many chapters should there be?”
My answer was/is, roughly, when the story is told, then you have the word count for story, chapters, and the number of chapters.
My opinion is that a story should have a beginning, middle, big scene, and end. Each chapter that helps lead you in that direction should have the same, beginning, middle, big scene, end.
I have read books that had some short chapters, and I think I remember, there was this one story that only had a one page chapter. Then there were stories that had chapters that could have been stand-a-lone books.
I know an author that shoots for 100k for his books, not sure what his goal for chapters is.
I have taken and split a large chapter into 2, since it seemed to add to the overall effect. I have also gone in and combined 2 chapters into one, again, because it seemed to add to the overall effect of the story.
Of course there are probably rules for all this, just as any english professor, or any editor.
All I can tell you, is that if I am reading a good book. There is no such thing as rules. If I am pulled into the story and don’t want to put down the book, I am not counting words or pages. I am just wrapped up on how the character is going to get into or out of the mess they are in.
Speaking of which, where did I set that book down!