I fielded a question earlier today about the right chapter length for novels. Others answered the question saying that there’s no right length. It depends on what the material calls for.
While that’s true, it’s not particularly helpful. There’s a saying about not breaking the rules until you understand the rules, and I think that goes for chapter length too. It’s eventually fine if you have short and long chapters, but until you have some writing experience, it’s good to have a rough outline of what’s appropriate.
My chapters tend to be between 5,000 and 7,000 words. They are usually composed of three scenes, because I tend to intertwine three different point of view (POV) characters. So my scenes tend to be anywhere from 1,200 words for a very short scene to 4,000 words for a very long scene, with most being in the range of 2,000 to 3,000 words.
(Since pages are arbitrary based on page size, font size, etc, it makes the most sense to think in terms of word count.)
If your chapters are short
If you find that your chapters are short, that doesn’t mean that you should add filler.
There shouldn’t be anything you think of as filler in a book. A good book is defined by having every word there for a purpose. Preferably two or three. Each scene should move the plot forward, or reveal something new about a character, or both.
Now it is possible that if you find your scenes or chapters to be very short that you need to practice getting more description down on the page. When I first started writing, I have a very vivid picture in my mind, but I only captured a tiny portion of that down on the page. So to a reader who didn’t already have the full picture on their mind, it seemed like all the action took place in a white room. Check in with your senses: are you describing what characters can see, hear, feel, smell, and taste? Does the reader know what the characters are thinking?
If your chapters are long
On the other hand, if your chapters tend to be too long, look for natural breaks in the action. Each chapter should have an arc: a problem, a journey to resolve the problem, and a resolution, or more commonly, a new problem. Of course, this is at a much smaller resolution than the arc of the book as a whole.