What the keyword tool checks
A useful KDP keyword decision needs more than a phrase list. Kindlefish combines demand signals with book-specific competition context so you can decide whether a keyword fits your reader, niche, and launch stage.
- Amazon keyword demand signals for book-related phrases.
- Competition context from books already visible in the niche.
- Confidence labels that separate stronger signals from weaker inferred signals.
- Backend keyword slot guidance that avoids obvious duplication and promotional claims.
How authors use it
Start broad, then narrow. Search the book's main promise, audience, genre, and problem phrases. Save the keywords that are relevant, reachable, and distinct from words already used in the title or subtitle.
What not to treat as a promise
Keyword volume and competition signals are decision support, not a ranking promise. Amazon ranking depends on conversion, reviews, category fit, pricing, cover, read-through, ads, and many other factors outside the keyword itself.
Questions authors ask
Can Kindlefish choose all 7 KDP backend keyword slots?
Yes, the paid Fee report can produce 7 suggested backend keyword slots. You should still review each slot against your title, subtitle, category, book content, and Amazon's current KDP rules.
Is this the same as SEO keyword research?
No. KDP keyword research is Amazon marketplace research for books. It overlaps with SEO, but the useful signals are reader intent, book-category context, and Amazon listing competition.
Next steps
Open the Kindlefish research workspace to run the live tool, or continue with one of the related author-research guides.