Word count is commonly used by translators to determine the price for the translation job.
All of these are average book word count ranges and should not be taken as the definitive word count you must reach in your book.
We all know of outliers within each genre that have been published well under, or well over, these word counts.
There are a wide variety of word counting tools available online.
As explained earlier, different word counting programs may give varying results, depending on the text segmentation rule details.