Amazon A9 Algorithm: Complete Guide for Sellers
Amazon A9 Algorithm: Complete Guide for Sellers
The Amazon A9 algorithm determines product search rankings on Amazon. For sellers, understanding A9 is essential to improve visibility, increase traffic, and drive sales. This guide outlines how A9 works, the factors that influence ranking, and practical actions sellers can take to optimize listings and performance.
How A9 works
Purpose: A9’s primary goal is to show shoppers the most relevant products that are likely to convert to a purchase. Relevance and conversion probability drive ranking for each search query.
Two-step process:
Retrieval — A9 finds a subset of products that match the search query using indexed fields (title, backend keywords, bullet points, product description, category, and more).
Ranking — Within that subset, A9 ranks products based on relevance and performance signals (conversion rate, sales history, pricing, availability, reviews, etc.).
Key ranking factors and seller actions
Relevance (on-page optimization)
Product title: Use clear, concise titles with primary keywords and essential attributes (brand, product type, size, color) in natural language. Avoid keyword stuffing.
Backend search terms: Fill backend keywords with additional relevant phrases, alternate spellings, and synonyms omitted from visible fields. Don’t repeat words or include punctuation; follow Amazon’s current character limits and rules.
Bullet points & description: Use bullets for main benefits and features; use the description for richer copy and secondary keywords. Focus on readability and buyer intent.
Product taxonomy & attributes: Select the most accurate category, subcategory, and fill out item specifics (color, material, size, model, etc.). Proper taxonomy improves retrieval and relevancy.
Images: Provide high-quality images that meet Amazon requirements (white background main image, additional lifestyle and detail shots). Images do not directly feed text indexing but significantly affect conversion.
Performance (conversion & sales signals)
Conversion rate: A9 favors listings that convert well for the given search. Improve conversion with optimized content, competitive pricing, compelling images, and strong social proof.
Sales history & velocity: Consistent sales volume and recent sales momentum boost ranking. Use promotions, deals, and advertising to generate traffic and sales velocity.
Click-through rate (CTR): Improve CTR with compelling titles, price, and main image. Good CTR signals relevance to A9.
Pricing & availability: Competitive pricing and consistent stock levels matter. Listings that are often out of stock or priced significantly higher than alternatives will rank lower.
Fulfillment method: Fulfillment by Amazon (FBA) often improves conversion because of faster shipping and Prime eligibility. Seller-fulfilled items can rank well if shipping and metrics are strong.
Reviews and social proof
Ratings & review count: Higher average ratings and more reviews increase buyer trust and conversion, which supports ranking.
Review quality: Address negative feedback promptly and maintain product quality. Use follow-up emails (within Amazon’s policy) to solicit legitimate reviews.
Early reviews: For new products, use programs like Amazon Vine (if eligible) and compliant launch strategies to build initial reviews and sales.
Advertising & external traffic
Amazon Ads: Sponsored Products, Sponsored Brands, and Sponsored Display ads drive visibility and sales that can improve organic ranking. Use targeted campaigns to boost impressions and conversions for key keywords.
Promotions & deals: Lightning Deals, coupons, and discounts increase clicks and sales velocity during the promotional period.
External traffic: Driving external traffic (social, email, influencers) can increase sales and conversion, signaling relevance to A9. Ensure tracking and compliance with Amazon’s policies.
Account health and operational metrics
Seller metrics: Maintain low order defect rate, late shipment rate, and cancellation rate. Poor account health can limit visibility.
Return rate: High return rates negatively affect listing performance. Reduce returns by clear product descriptions and proper images.
Policy compliance: Suspensions or restrictions can remove listing visibility. Always follow Amazon’s rules for product content, pricing, and promotions.
Technical and strategic considerations
Keyword research: Use a mix of broad, phrase, and exact-match keywords. Prioritize keywords by search volume and relevance. Regularly update based on traffic and conversion data.
A/B testing: Test titles, images, bullets, and backend keywords. Use experiments where available to measure impact on clicks and conversion.
Listing maintenance cadence: Review and optimize listings regularly (monthly or after significant changes in performance). Monitor search terms reports, backend search term effectiveness, and customer search behavior.
Global/local marketplaces: Tailor content and keywords for each marketplace (language, metrics, regional preferences). Use local best practices and compliance rules.
New product launches: Combine optimized listings, targeted ads, early review
