This is a nice little article from Writer's Digest explaining general industry word-count expectations from the agent perspective.
How Long Should a Book Be? Word Count For Books Explained - WritersDigest.com
The article covers several genres. To quote what it has to say about our own -
The whole article is well worth the read, though.
How Long Should a Book Be? Word Count For Books Explained - WritersDigest.com
The article covers several genres. To quote what it has to say about our own -
Science fiction and fantasy are the big exceptions because these categories tend to run long. It has to do with all the descriptions and world-building in the writing.
With these genres, I would say 100,000 – 115,000 is an excellent range. It’s six-figures long, but not real long. The thing is: Writers tend to know that these categories run long so they make them run really long and hurt their chances. There’s nothing wrong with keeping it short (say, 105K) in these areas. It shows that you can whittle your work down.
Outside of that, I would say 90K-100K is most likely all right, and 115-124K is probably all right, too. That said, try to keep it in the ideal range.
The whole article is well worth the read, though.