How to Choose KDP Keywords and Categories (2026 Guide)

How do KDP keywords work?

When you set up a book, KDP gives you seven keyword fields. Each field accepts up to fifty characters, and each should hold a short phrase, not a single word. Amazon combines these with your title, subtitle, categories and description to decide which searches your book can appear in.

That means you should not waste a slot repeating words already in your title or subtitle. If your title is Murder at Marsh House, a keyword of murder mystery book adds little. A phrase like cosy village mystery with amateur sleuth adds new information.

Keywords do not guarantee a ranking. They make you eligible to appear. Whether you actually show up high depends on how well the book sells and converts for that phrase, which is why choosing phrases you can realistically win matters more than choosing popular ones.

Why do long-tail phrases beat single words?

A single word like romance is shared by an enormous number of books, so you will never surface for it. A phrase like small town enemies to lovers romance is what a motivated reader types, far fewer books target it, and you have a real chance of appearing in the first results.

Long-tail phrases also bring better-matched readers. Someone searching a specific trope, setting or problem already knows what they want, so they click and buy at a higher rate than a casual browser. Higher conversion then helps your book rank for that phrase over time.

Build phrases from the things your reader actually says: the trope, the setting, the era, the mood, the problem your non-fiction book solves, or the type of reader it suits. Those specifics are where an independent author can win.

How do you research what readers really search for?

Start with Amazon's own search bar. Type the beginning of a phrase that describes your book and note the suggestions that appear. These come from real shopper behaviour, so they are more trustworthy than guesses. Try the same start with different endings, such as the setting, the trope or the problem, and keep a running list.

Next, look at books that sit next to yours. Search for your closest comparable titles and read their titles, subtitles and descriptions to see the language readers and authors in your niche use. Do not copy another author's name into your keywords, but do borrow the vocabulary. The Comp Title Finder can help you identify books that sit in the same space.

Then sort your list. Keep phrases that accurately describe your book, discard ones that are too broad or only loosely related, and rank what is left by how specific and honest it is. If you want a head start on ideas, the KDP Keyword Generator can produce candidate phrases to test against what you see in the search bar.

What does a good set of seven keywords look like?

Imagine a standalone cosy mystery set in a Cornish bakery. Seven strong slots might cover different angles rather than repeating one idea: the sub-genre and setting, the type of sleuth, the central trope, the mood, the reader it suits, the series style, and a specific plot element. Each slot is a different door into the same book.

Spread your slots across angles because Amazon combines words across fields. You do not need to write every possible word order. Covering setting, trope, mood and reader type in separate slots gives you more combinations than seven near-identical phrases would.

Write each phrase so it makes sense to a human, then check it fits in fifty characters. Avoid commas and filler such as the or best, which add nothing. Keep a note of exactly what you entered so you can compare results when you change it later.

What should you avoid in keywords?

• Do not repeat words already in your title, subtitle or category. Amazon already uses them.
• Do not use other authors' names, brand names or trademarked terms. Amazon prohibits it, and it can lead to your book being suppressed or your listing being flagged.
• Do not use misleading terms, such as a popular genre your book is not, or claims like bestseller or free. They attract the wrong readers and lead to poor reviews and returns.
• Do not stuff in misspellings or unrelated popular words. They waste a slot and rarely help.

Every slot is limited, so spend all seven on honest, specific phrases that describe the book a reader will actually receive.

How do KDP categories work and how many can you choose?

At publishing, KDP lets you choose up to three categories for a book. Amazon's public store has a much larger browse tree than the list you pick from, and a book may appear in more places than the three you chose. Ebook and print editions are set up separately, so check both formats rather than assuming one carries over.

Categories matter for two reasons. They tell Amazon and readers what kind of book this is, and they define the bestseller lists your book competes on. The right category puts you in front of browsing readers, while the wrong one hides your book or sets you against far bigger names.

If the category list in KDP does not offer the niche you want, KDP Support has historically been able to add a book to extra categories on request. Policies change, so check KDP's current help pages before relying on it.

How do you choose categories you can actually rank in?

Choose the most specific sub-category that honestly describes your book. Open the live Kindle Store, find that category and look at the bestseller list. Ask whether books like yours are there, and whether the books near the top are so established that you could not realistically reach them. The Amazon Category Finder can help you map your book to category paths.

Compare, do not guess. Look at the sales rank of books sitting at the lower end of that category's top list. If they have a strong overall rank, the category is competitive. If books with a modest overall rank appear on the list, a well-launched book has a better chance. Exact thresholds shift constantly, so judge by comparison on the day you look.

Mix your three choices. One can be a broader category that clearly describes your genre, and the others narrower niches where you can reach a visible rank. Never pick a category just because it is quiet. A mismatched category misleads readers and can hurt your reviews more than a crowded category would.

How do you know if your keywords and categories are working?

Check your listing from a clean browser. Search for your key phrases and see whether your book appears, and where. Look at your category rank on the product page and note how it moves after sales. Keep the dates alongside your notes, since a ranking only means something compared with a previous check.

If you run Amazon Ads, the search term report shows the phrases real shoppers used before clicking or buying. That is useful evidence for new keyword ideas. The how-to-run-amazon-ads-for-books guide covers this in more detail, and the Amazon Ads ACoS Calculator helps you judge whether a phrase is paying for itself.

Change things deliberately. Alter one or two slots at a time, wait long enough to see a pattern, and record what you did. Constant rewriting makes it impossible to tell what helped. Revisit your choices after launch, after a promotion, or when the store layout changes. CruxOne also offers a wide set of free author tools at cruxone.io/tools if you want more help while you do this.

Frequently asked questions

How many keywords does KDP allow?

Seven keyword fields, each up to fifty characters. Each should hold a multi-word phrase a real reader might search, not a single word.

Should I repeat words from my title in my keywords?

No. Amazon already uses your title, subtitle and categories, so repeated words waste space. Use the slots for new angles such as trope, setting or reader type.

How many categories can I choose on KDP?

Up to three when you publish. Amazon may show the book in additional places, and ebook and print editions are set up separately.

How do I get a bestseller badge?

Reach the top of a category's bestseller list during a sales spike. Narrow, honest sub-categories make this far more achievable than broad ones.

Can I use another author's name as a keyword?

No. Amazon prohibits other authors' names and trademarked terms in keywords, and your book may be suppressed or flagged if you use them.