How to do keyword research for Amazon KDP

Keyword research for Amazon KDP (Kindle Direct Publishing) is unique because it’s not about ranking on Google, but on Amazon’s internal search engine.

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Authors need to understand what potential readers are typing into the Amazon search bar to discover books.

This involves identifying keywords that readers use to find books by genre, topic, theme, problem solved, or even specific character types.

The goal is to maximize discoverability within the Amazon ecosystem, leading to more book sales.

Understanding Amazon A9 Search Algorithm

Paragraphs: Amazon’s search algorithm, A9, is designed to maximize sales. It prioritizes relevance and sales velocity. For KDP keyword research, this means you need to identify keywords that not only describe your book accurately but also align with what active buyers are searching for. It’s less about broad informational queries and more about transactional or commercial investigation intent. A9 considers factors like keyword relevance in the title and subtitle, categories, customer reviews, sales history, and click-through rates. Therefore, your keywords must directly resonate with the purchasing intent of the Amazon customer.

• If your book is a cozy mystery, readers might search “cozy mystery small town,” “cat detective mystery,” or “baking mystery series.”
• For a non-fiction self-help book, searches could be “overcome anxiety techniques,” “mindfulness for beginners,” or “daily meditation guide.”
• Sales-driven intent: Keywords that indicate a reader is ready to buy.
• Specificity: Amazon searches tend to be more specific than general web searches.
• Categorization: Keywords help Amazon categorize your book correctly.
• Read-alikes: Readers often search for books similar to ones they enjoyed (e.g., “books like Harry Potter”).
• Problem/Solution: For non-fiction, users search for solutions to their problems.
  Bold Text: Amazon’s A9 algorithm prioritizes keywords that lead to sales and customer satisfaction.

Leveraging Amazon Search Bar Autocomplete

Paragraphs: The simplest and most direct free tool for Amazon KDP keyword research is the Amazon search bar itself. As you type in a broad genre or topic, Amazon’s autocomplete feature will suggest popular and relevant search terms. These suggestions are based on real customer searches on the platform, indicating active demand. This is particularly effective for uncovering long-tail keywords and niche opportunities that readers are actively using to find books like yours. Try variations of your core topic, and observe what Amazon suggests.

• Start typing “fantasy novel.” Autocomplete might suggest “fantasy novel epic,” “fantasy novel young adult,” “fantasy novel series,” “fantasy novel for adults.”
• Type “keto cookbook.” Suggestions might include “keto cookbook for beginners,” “keto cookbook air fryer,” “keto cookbook diabetes.”
• Start with broad terms: Begin with your book’s genre (e.g., “romance,” “thriller,” “self-help”).
• Add modifiers: Experiment with adding words like “best,” “new,” “guide,” “for beginners,” “quick,” “series.”
• Niche down: If your book is “historical fiction,” try “historical fiction medieval,” “historical fiction WWII,” “historical fiction romance.”
• Observe full suggestions: Let the autocomplete run its course and note down all relevant phrases.
• Iterate: Take a suggested keyword and type it back into the search bar to find even more granular terms.
  Data/Stats: While no direct search volume data is given, the order of suggestions in Amazon’s autocomplete generally reflects their popularity among Amazon customers.

Analyzing Best-Selling Books and Categories

Paragraphs: Studying the titles, subtitles, categories, and keyword choices of best-selling books in your genre is an incredibly effective strategy. Amazon provides various “Best Sellers” lists (by genre, sub-genre, and even niche categories like “Amateur Sleuth Mysteries”). Analyze the keywords these successful books use in their titles, subtitles, and descriptions. Look at the language that resonates with readers. Pay attention to the categories they are listed under, as these are often highly relevant keyword phrases in themselves. This isn’t about copying but about understanding the winning formulas and identifying common search patterns used by your target audience.

How to do keyword research in Semrush

• If you’re writing a science fiction book, browse the “Science Fiction Best Sellers.” Do authors use terms like “space opera,” “dystopian,” “first contact,” or “alien invasion”?
• For a weight loss book, look at the titles of top sellers. Are they using “keto,” “intermittent fasting,” “plant-based,” “beginner’s guide,” or “meal plan”?
• Navigate to Amazon’s “Best Sellers” page and find your relevant categories/sub-categories.
• Examine Titles and Subtitles: Note keywords used by top-ranking books.
• Read Descriptions: See how best-selling authors describe their books and the keywords they include.
• Check “Look Inside”: Scan the table of contents or first few pages for common terms.
• Review “Customers Also Bought”: This section on product pages reveals related books and potential keywords.
• Identify Amazon Categories: Pay attention to the specific categories best sellers are listed under, as these are important for discoverability.
• Read Reviews: Customer reviews often contain the exact language readers use to describe what they liked or were looking for, providing valuable keyword insights.
  Bold Text: Best-selling books on Amazon provide real-world examples of keywords that convert into sales.

Using Amazon Ads (AMS) Keyword Data

Paragraphs: If you plan to run Amazon Ads (AMS), the platform’s internal keyword suggestions are incredibly valuable. While this isn’t strictly “free,” the data obtained from experimenting with small ad campaigns or using their keyword suggestion tools before launching is worth the minimal investment. Amazon Ads will show you estimated bid ranges and potentially even estimated search volumes for keywords on their platform. This is a direct insight into the commercial viability and competitiveness of keywords for book discovery and sales on Amazon.

• When setting up an AMS campaign, Amazon will suggest keywords based on your book’s title, description, and category. These suggestions are usually highly relevant and actively searched.
• You can also manually input keywords and see their estimated bid costs, which can tell you which terms are most competitive (and thus likely most lucrative).
• Automatic Targeting (for insights): Launch a small automatic targeting campaign to see which customer search terms trigger your ads. This is essentially free keyword research if your budget is minimal.
• Manual Targeting > Keyword Suggestions: When setting up a manual campaign, Amazon provides keyword suggestions based on your book.
• “Search Term Report” (post-launch): After an ad campaign runs, this report shows the exact queries customers used to click your ads, providing direct evidence of converting keywords.
• Refine with negative keywords: Use the Search Term Report to identify irrelevant searches and add them as negative keywords to your campaigns.
  Data/Stats: Amazon Ads provides valuable data on impressions, clicks, sales, and Advertising Cost of Sales (ACOS) for each keyword, allowing you to identify which keywords are driving actual book sales.

Optimizing KDP Keywords in Title, Subtitle, and 7 Backend Slots

Paragraphs: Amazon KDP allows authors to input up to seven backend keywords. These are crucial for discoverability, as they are not visible to readers but are used by Amazon’s A9 algorithm to index your book. Additionally, your title and subtitle are the most important keyword real estate. You should strategically include your primary, high-volume keywords here. The goal is to maximize the number of relevant search terms your book can rank for, covering all possible ways a reader might search for your specific content. Combine broad terms with specific long-tail keywords, and use synonyms, different spellings, and related concepts.

How to do keyword research on Pinterest

• Title: “The Baker’s Secret: A Small-Town Cozy Mystery” (Primary: “Cozy Mystery,” “Small-Town Mystery”)
• Subtitle: “A delightful tale of love, pastries, and a surprising murder for amateur sleuth fans.” (Secondary: “amateur sleuth,” “baking mystery”)
• Backend Keywords: culinary suspense, village murder, detective female, historical cozy, tea shop mysteries, book club read, clean mystery romance
• Title: Include your absolute most important 1-2 keywords here.
• Subtitle: Use 2-3 strong secondary keywords and descriptive phrases.
• Categories: Select the most relevant categories and sub-categories.
• 7 Backend Keywords:
  • Use all seven slots.
  • Avoid repeating keywords already in your title/subtitle.
  • Mix broad terms with highly specific, long-tail phrases.
  • Include synonyms, common misspellings (if relevant), and related concepts.
  • Think of character types, settings, themes, plot points.
  • For non-fiction: problems solved, benefits, target audience.
• Series keywords: If part of a series, include terms like “book 1,” “series name,” etc.
• Author name: Some authors include their name as a backend keyword, especially if they have a large following.
  Bold Text: Maximize your title, subtitle, and all seven backend keyword slots with a diverse mix of relevant and high-intent terms. Each slot is an opportunity for discovery.