Choosing KDP categories: a step-by-step method

Categories are the shelves of Amazon’s store. Readers browse them, bestseller lists are built from them, and they tell Amazon who your book is for. Choosing them takes an hour or two of research, and it’s one of the few decisions in a listing that affects how your book is found from the first day.

How categories work on KDP now

When you set up a book, KDP lets you select three categories. Each format is set up separately, so your ebook and paperback each get their own three, and the category trees differ between the Kindle Store and the Books store. Some categories are available only for certain formats or marketplaces.

A few rules from KDP’s help pages are worth knowing:

• You can change categories at any time from your Bookshelf by editing the book’s details. Changes can take up to 72 hours to appear.
• Misleading categories aren’t allowed. KDP says it doesn’t tolerate categorization that misleads readers, and it may remove or change a category that doesn’t fit the book.
• Older advice is out of date. Before 2023, KDP had authors pick two BISAC subject codes and let them request extra categories through support. That system was replaced by the direct choice of three categories, so guides that tell you to email for ten categories no longer apply.

Why the choice matters

Categories do three jobs:

1. Browsing. Readers who like a subgenre click through to its shelf and its bestseller list.
2. Ranking. Your book’s rank in its categories appears on the product page. Ranking near the top of a category puts the book in front of browsing readers, and a book that ranks first in a category can display a “Best Seller” badge.
3. Signals. Categories tell Amazon which readers to show your book to, alongside your keywords, description, and sales history.

A category that fits brings readers who want your book. A category chosen only because it looks empty brings readers who don’t, and that shows up in your sales and your reviews.

A method for choosing

1. List comparable books

Find 5 to 10 books that a reader of yours would also enjoy: same subgenre, similar tone, similar audience, published in the last few years. Recent books matter, because categories and reader tastes change.

2. Read their category ranks

On each product page, scroll to the product details. The “Best Sellers Rank” shows the book’s overall rank and its rank in up to three categories. Note every category path that appears. Paths that recur across several comparable books are strong candidates.

3. Walk the tree yourself

Open the Kindle Store for your ebook, or Books for your paperback, and browse from the top level down to the subcategories. Note neighbors you hadn’t considered. Sometimes a more precise shelf exists one level deeper than where your comparable books sit.

4. Test each candidate for fit

Open the bestseller list for each candidate category and look at the top 20 books:

• Would a reader of these books want yours?
• Do the covers and descriptions signal the same genre and tone?
• Is the audience the same: adult, young adult, or children’s?

If the answer to any of these is no, drop the category, however tempting its competition looks.

5. Weigh the competition

For the categories that fit, compare how competitive they are. Look at the overall Best Sellers Rank of the books near the bottom of the top 20. If even those books have very strong overall ranks, the category is crowded, and a new book will struggle to appear on its list. If they have much weaker ranks, there’s more room. You don’t need exact sales estimates for this; you’re comparing categories with one another.

6. Choose a mix

A sensible set of three often includes:

• One accurate, broader category where your book clearly belongs
• One or two narrower categories where it fits closely and the competition is lighter

7. Repeat for the other format

Your paperback’s category tree is different from your ebook’s. Run the same steps there rather than assuming the ebook choices carry over.

A worked example

For a hypothetical cozy mystery about a baker who solves crimes in a seaside town, research might produce candidates like these. The names are illustrative, so check the current tree, because Amazon renames and reorganizes categories.

• Mystery > Cozy > Culinary
• Mystery > Cozy > Animals (only if a cat or dog plays a real part in the story)
• Mystery > Women Sleuths

The culinary shelf fits closely. The animals shelf belongs on the list only if the pet matters to the plot; otherwise it misleads readers who choose books for exactly that reason. The women sleuths shelf is broader and more competitive, but accurate.

If the research turns up more than three good candidates, keep the extras in your notes. When you revisit your categories after launch, or when the next book in the series comes out, they’re ready to test.

Categories for nonfiction

The same method works for nonfiction, with one extra question: does the category match the reader’s problem, or only your subject? A book on budgeting for freelancers might fit a personal finance shelf and a small business shelf. The right choice depends on which readers the book actually serves, which your description and subtitle should make obvious too. Readers on a professional shelf expect a different tone and depth from readers on a general self-help shelf.

When to change your categories

Categories aren’t permanent, and a few signals suggest it’s time to revisit them:

• The “customers also bought” books don’t match your shelves. The books shown alongside yours reveal which readers Amazon associates with it. If they cluster in a subgenre you didn’t choose, that shelf may fit better.
• Reviews describe a different book. If readers keep calling your “thriller” a domestic drama, they’re telling you what shelf they expected.
• You never appear on any category list, even during a promotion. A slightly narrower category may give the book a chance to be seen.
• A new category appears that fits your book more precisely than anything available when you published.

Change one or two categories at a time and give each change a few weeks, so you can tell what made a difference.

Mistakes to avoid

• Choosing an unrelated empty category to win a bestseller badge. It’s against KDP’s rules and brings the wrong readers.
• Picking only broad categories like general fiction, where a new book won’t appear on the list.
• Mixing audiences. Putting an adult book in a children’s category, or the reverse, causes real problems for readers and for you.
• Forgetting the paperback. It needs its own research.
• Never revisiting. Check your categories after launch, and again when you release the next book in a series.

Category checklist

• 5 to 10 recent comparable books reviewed
• Candidate paths collected from product pages and from browsing
• Top 20 of each candidate checked for fit
• Competition compared across candidates
• Three categories chosen for the ebook and three for the paperback
• A dated note of the choices, to review after launch

Keywords and categories work together but do different jobs. If you haven’t filled your keyword slots yet, see how to fill KDP’s seven keyword slots.

AIBookWriter’s free KDP Category Finder reads your book description and suggests categories that fit, with the reason for each. Treat its list as a set of candidates, and check each one against the comparable-books test above.