KDP Keyword Research Tool
Brainstorm long-tail keyword phrases for your book and plan all 7 of Amazon KDP's backend keyword slots. Combine a seed term with buyer-intent modifiers to surface phrases real shoppers type.
No fake numbers. This tool helps you generate and organize keyword ideas — it does not display search volume or competition scores. Amazon does not publish that data, so any tool showing “exact KDP search volume” is estimating. Validate demand for free using Amazon's own search-bar autocomplete (see the tips below).
33 keyword ideas
Tap a phrase to add it to a slotYour 7 KDP Keyword Slots
0 / 7 filledAmazon gives you seven backend keyword fields, each up to 50 characters. Fill them with distinct phrases — don't repeat words already in your title or subtitle, and don't repeat the same word across slots.
Why Keywords Matter on KDP
Keywords are how Amazon decides which searches your book can appear in. Your title, subtitle, and 7 backend keyword fields all feed the search index. Strong, specific keywords put your book in front of shoppers who are ready to buy; vague or repeated ones waste the limited space you get.
The biggest wins on KDP come from long-tail phrases — three- to five-word searches like “large print sudoku for seniors” rather than just “sudoku.” They have less competition and signal exactly who the book is for, so the shoppers who find you are far more likely to buy.
Keywords also influence which browse categories your book can be placed in. Some categories are only reachable through specific keyword phrases, so smart keyword choices can unlock more “Best Seller” category slots.
How to Validate Keywords for Free
- 1
Generate ideas above
Start with your core topic and mix in audience, format, benefit, and occasion modifiers to build long-tail candidates.
- 2
Test them in Amazon's search bar
Type each phrase into the Amazon search box. The autocomplete suggestions are real, popular searches — if Amazon suggests your phrase, shoppers are typing it.
- 3
Scan the competition
Search the phrase and look at the results. A page of weak covers and few reviews signals an opening; a wall of bestsellers means it's crowded.
- 4
Fill your 7 slots with distinct phrases
Use the planner above. Avoid repeating words from your title and don't reuse the same word across multiple slots — it's wasted space.
- 5
Skip prohibited terms
Amazon bans subjective claims (‘best’, ‘free’), other authors' or brand names, and time-sensitive terms like ‘new’ in backend keywords.
Common Keyword Mistakes
Repeating title words in the backend
Amazon already indexes your title and subtitle. Repeating those words in the 7 slots wastes space — use the slots for new phrases instead.
Using single broad words
‘Journal’ or ‘cookbook’ alone is impossibly competitive. Long-tail phrases convert better and rank faster.
Stuffing one slot with commas
You don't need commas. Amazon treats the whole field as a phrase pool, so use the full 50 characters for natural multi-word phrases.
Including banned terms
Subjective claims, other brands/authors, and time-bound words can get your book suppressed. Keep keywords descriptive and factual.
Never revisiting keywords
Search trends shift. Review and refresh your keywords every few months, especially if sales stall.
Put these keywords to work
KDP Builder takes you from this free tool to a complete, upload-ready package — manuscript or interior, cover, and metadata.
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Keep prepping your book — every tool below is free and needs no signup.
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Ready to Build the Whole Book?
Take it further with a complete, Amazon-ready project in KDP Builder.