Really depends on the type of book your writing, there is multiple guides online that I found, the below is a general list,
Within the world of literary fiction, different genres follow more specific word count targets:
1. Thriller: A good suspense story has to keep the plot moving to keep the reader engaged. The ideal count for a mystery is a 70,000 and 90,000 word novel.
2. Science fiction and fantasy: Sci-fi novels are an art in world-building. The need to invent a completely new environment makes this genre longer than others. A fantasy novel will usually have 90,000 to 120,000 words.
3. Romance novels: Not every love story is an epic like Wuthering Heights. Romantic plots now tend to be fun, fast reads. Some are as short as 50,000 words—the perfect book for a beach vacation. The high-end romance novel word count is 100,000.
4. Historical fiction: Fleshing out an imagined historical world lends itself to a higher word count, so historical fiction tends to be closer to 100,000 words.
5. Non-fiction: There is no definitive word count guide for non-fiction books due to the many subgenres. If you’re writing a non-fiction book, be sure to look up that category to find the length of similar books. For example, memoirs are generally 80,000 to 90,00 words.
Source -
https://www.masterclass.com/articles/word-count-guide#how-long-should-a-novel-beand
Source -
https://www.writersdigest.com/whats-new/word-count-for-novels-and-childrens-books-the-definitive-post