How to Fill in Your 7 Amazon KDP Keyword Boxes
A data-backed approach to filling the seven KDP keyword boxes so your book gets indexed for more searches, ranks stronger for the keywords that work, and stays in the right category.
Introduction
When you go to publish your book on KDP, you will see seven boxes where you can enter your seven Kindle keywords.
Amazon allows you to enter up to 50 characters in each box, including letters and spaces. This leaves authors wondering whether they should write one keyword in each box, or fill each box with as many words as possible.
what is the best way to fill those seven boxes so your book shows up more on Amazon and makes more sales?
Over the past 12 years of self-publishing, I’ve learned this lesson through trial and error, publishing dozens of books, and paying close attention to what actually works on Amazon. One of the most valuable tools that helped me understand this process was Publisher Rocket, a powerful book marketing tool that provides real data about keywords, competition, and discoverability. By combining my own real-world publishing experience with the insights available through Publisher Rocket, I was able to identify the most effective way to structure keyword boxes so your book indexes properly, ranks higher in search results, and ultimately reaches more readers on Amazon.
Understanding Indexing and Ranking
Indexing
Indexing is when Amazon acknowledges that your book should appear for a specific keyword or keyword phrase.
When someone types a keyword phrase into Amazon, you will see the total number of books that appear for that phrase. This means those books are indexed for that keyword.
Ranking
Ranking determines where your book appears in those search results.
The higher your ranking, the more clicks and potential sales you receive.
Ranking determines how much visibility you get.
Key Findings
Here’s what the experiment revealed.
More words increase indexing. More words = more chances for Amazon to connect your book to searches.
Amazon creates keyword combinations. It rearranges your words into multiple searchable variations.
Too many words can weaken ranking strength for a specific phrase (less “focus” initially).
Keywords influence category placement. Amazon may shift your category based on your keyword choices.
Example: How Amazon Rearranges Keywords
If you enter words like:
Amazon may index you for combinations such as:
hot romance
wild romance
wild betrayal
wild summer romance
hot betrayal romance
Additional Important Facts About Keyword Boxes
- Duplicate words in keyword boxes do not improve ranking, but they do not hurt you either.
- Keywords in your title and subtitle carry significantly more weight than keywords in your keyword boxes.
- Amazon will not rank your book for words or phrases it does not recognize as valid search terms.
- Simply placing a word in a keyword box does not guarantee indexing. Amazon must recognize it as legitimate.
The Optimal Keyword Box Strategy
The most effective strategy divides your seven keyword boxes into three sections — so you get reach and focus.
Dedicate three keyword boxes to specific keyword phrases you want to rank highly for.
Box 1: wholesome second chance romance
Box 2: small town clean romance
Box 3: single mom love story
Leave the rest of the box empty. This strengthens your ranking power for that exact phrase.
Use two keyword boxes to include additional relevant words and phrases. These are not your primary ranking phrases, but they still describe your book.
Separate words with spaces only.
clean romance sweet romance family drama feel good love story
second chance love small town fiction emotional romance women fiction
Notice how these boxes are packed with relevant words. Amazon will rearrange them into multiple combinations, increasing indexing reach.
Use the final two boxes for phrases strongly tied to your target category. Amazon uses these to help determine category placement.
Box 6: clean and wholesome romance
Box 7: sweet small town romance
Box 6: cozy mystery series
Box 7: amateur sleuth mystery
Box 6: kindle direct publishing guide
Box 7: self publishing for beginners
If you cannot identify strong category phrases, use additional relevant keyword phrases instead.
Final Outcome of This Strategy
- Your book indexes for more keywords.
- Your book ranks better for your most important keywords.
- Your book remains properly categorized.
This increases discoverability, visibility, and sales potential.
Conclusion
This keyword strategy helps Amazon understand your book more clearly.
- What your book is about
- Where to place your book
- When to show your book to readers
By following this strategy, you increase the likelihood that readers will find your book.