What is Amazon’s A9 algorithm and how does it work?

In a marketplace as highly saturated and deeply competitive as Amazon’s, it can seem difficult, or even impossible, to improve the ranking and visibility of your products. However, if you know the A9 algorithm and know how to implement a good effective SEO strategy on Amazon, you will be able to increase the visibility of your products until they are among the first search results in their category.

If you don’t have an in-depth knowledge of Amazon’s A9 search engine and have a good understanding of all its nuances, you will not only be losing traffic and sales, you will also be going unnoticed by the competition, missing the opportunity to raise awareness of your product and your brand.

In this how-to guide, we’ll provide you with information to help you understand how Amazon’s A9 algorithm works and what the best practices are for achieving higher rankings.

What is Amazon SEO in relation to algorithm 9?

SEO (Search Engine Optimization) stands for Search Engine Optimization. It is the process of increasing the quality and quantity of traffic that is generated from the organic search results displayed by search engines. Although the most well-known search engine currently is Google’s, Amazon’s (A9) works quite differently.

How Amazon’s A9 Search Algorithm Works

Amazon’s algorithm is known as A9. If you do a search on Amazon, you’ll be using the A9 search engine. To perform a search at scale, Amazon’s search engine and algorithms determine which items best match the customer’s query and score them based on how relevant they are to the consumer.

Amazon’s ranking algorithms automatically learn to combine multiple relevance features. They analyze past search patterns to tailor to what’s most important to customers. As we mentioned earlier, Amazon searches are transactional and not informational.

When you upload a product to Amazon (indexing), the algorithm mostly reads the title, search terms, and category node by which you indexed it. From there, rank your product for different search terms. Keep in mind that this won’t make your product rank higher, but it will rank higher within its category.

The A9 search algorithm is based on two basic principles:

Performance and relevance. Amazon charges you a commission for every sale you make, and therefore its A9 algorithm is designed for you to make higher profits. The more sales your product generates (and the more money Amazon makes), the better you’ll rank for search terms you’ve already converted with.

The three main features of Amazon A9 are:

Index, classify and offer the most relevant results (those that generate the most sales and commissions) to the customer’s search term. Therefore, although it is essential to generate good keyword research so that your product is classified with the right keywords, the most important thing to position it well will be sales.

Another thing you should never forget is stock. Remember that Amazon’s goal is to sell and, therefore, it will not position your products with low stocks or that break stock. Breaking stock will be like going back to square one as far as positioning is concerned. Be very careful with this DOOS (Days Out Of Stock) metric: That negative metric can be one of the reasons why your product doesn’t show up in searches.


Consider how much money Amazon is making from your product. The more sales you generate, the more profit Amazon will have and the more priority it will give to products that have a better conversion rate.


Reviews and ratings are highly relevant when it comes to improving the organic positioning of your products. They will give you authority over competing articles. The more reviews and better rating your product gets, the more its conversion rate will increase. We could say that reviews on Amazon are the equivalent of links on Google. The more you get and the better quality they are, the more authority and relevance the algorithm will give you.

Remember: Amazon rewards listings that work, not listings full of keywords.


Being on the first page of Amazon will ensure visibility. If your product card is relevant, you will generate sales, and if your product is of quality, you will receive good reviews. The vast majority of product clicks, in a marketplace as broad as Amazon’s, take place on the first page of search results, underscoring the critical importance of being on that first page.
The question then becomes: How do I get on the first page of results if my product is new, I don’t have reviews, and I haven’t generated sales?

You’ll need to design a good launch strategy that generates your first sales through Amazon Advertising campaigns, offers, coupons, and promotions. It’s important to be clear about the goals of your Amazon Advertising campaigns. If in the launch phase you are overly concerned about KPIs such as ACOS, you will only be measuring how profitable your CAMPAIGN NOW is, but you will not be measuring how profitable your ACCOUNT WILL be later.


Carlos Sanchez

Head of Marketing Strategy | Nozama Solutions