Understanding the A9 Amazon Search Algorithm

Any brand hoping to improve its Amazon search ranking needs to be familiar with the site’s proprietary search algorithm: A9. Even though Amazon is the most popular source for researching and searching for products online, its business is selling those products, which is why A9 functions a bit differently than Google. Understanding the functional differences between Amazon search and other algorithms is important for brands looking to succeed on the platform.

Because Amazon is primarily interested in making money, the A9 algorithm is configured to increase revenue, not facilitate research. Whereas traditional search engines need to worry about “how to” informational searches, the goal of the A9 search algorithm is to put customers in front of something they are likely to buy as quickly as possible.

Once brands understand exactly how Amazon search works, they can begin to tailor their content to give the algorithm exactly what it is looking for.

Amazon Search from a Brand Perspective

First off, brands should know that conquering the A9 algorithm can be complicated, no matter how many best practices it follows. This is because Amazon search is rooted not only in relevant keywords, but also on sales numbers and other factors that aren’t easy to control.

Amazon search is based on two core principles: relevance and performance. Relevance is something brands can control almost completely. Creating informational product pages that are populated with thoughtful and relevant SEO keywords is the cornerstone of ensuring products are relevant to the A9 algorithm, and every brand has the power to accomplish this.

Performance is trickier to master. For these metrics, the algorithm examines a variety of data points including sales rank, price, ability to fulfill orders, and sales velocity. Based on these metrics, as well as the search history of the customer, Amazon chooses whether or not the customer is more likely to purchase your product or the products of your competitors, and ranks search results accordingly.

Amazon search rewards products that are already selling well by placing them at the top of the search results, which then helps products sell more units. For brands that aren’t already top sellers in their categories, figuring out how to increase conversations without dominating Amazon SERPs is the toughest nut to crack, but it is essential for giving the A9 algorithm what it wants to see in order to serve your product to potential buyers.

Examples of the A9 Search Algorithm in Action

After a very wet winter camping trip in which my rain jacket and pack soaked through, I decided to invest in a waterproof poncho. As many humans do these days, I began my product research journey on Amazon. I wanted something that could keep me and my pack dry when conditions got bad on long hiking trips where I was already carrying a lot of weight, so I searched for a specific set of keywords: “lightweight waterproof backpacking poncho.”

Amazon search

The product I ended up buying was placed high in the search results, but not at the top. Looking at the way my search terms are spread throughout the title and bullets, this product seems like a pretty good match. It doesn’t specifically call out “backpacking,” but it does say that it is big enough to cover a “backpack,” which is what I was after. Synonyms in the copy like “mountaineering,” “hiking,” and “outdoor activities” make sure a lot of ground is covered for those who are searching for outdoor rain protection.

But search terms aren’t the only reason this product was shown to me. It also has a 4+ star rating with 1313 reviews, it ships for free with Amazon Prime or orders over $25, and it only costs $18.99. The Amazon search algorithm loves these three factors, and rewards products that have the same success and ready availability.

Looking back at my query, I was surprised that my first (and perhaps most important) term, “lightweight,” was nowhere to be found in the title or bullets. Doing a quick search for the word on the page though, it came up multiple times—in the customer reviews. As I was researching which poncho to buy, customer reviews were arguably the most important product page resource for me, and glowing reviews were the reason I ended up making this particular purchase. Well, that and the fact that I specifically wanted this color of green: I don’t want to wear some neon-colored garbage bag out on the trail.

Tips for Using the Amazon A9 Search Algorithm to Your Advantage

  • Strong sales start with exceptional content. Using keywords in your essential content can lead to higher search rankings, and remains one of the only ways to improve your standings without paying Amazon for the privilege.
  • Pay attention to the basics. Product titles are the first, and possibly last, words that a customer sees about your product. They need to be finely crafted to give customers exactly the information they need, and nothing they don’t.
  • Use your bullet points wisely. This invaluable “above-the-fold” content is one of the main ways Amazon search can decipher the relevance of your product. This is a great place to use inject smart and relevant SEO keywords, but never at the expense of readability.
  • Improve your sales with Amazon Advertising. A strong marketing strategy with Amazon Advertising is the most effective way to increase sales, which in turn increases sales rankings.
  • Remember that quality content is integral to Amazon Advertising too. There’s no point in paying to advertise pages that aren’t optimized to convert.
  • Optimize your Amazon Advertising search terms. Make sure that you’re taking advantage of backend search terms to drive the most customers possible to your pages, and while you’re there, set negative keywords as well. You don’t need to advertise your maxi pads on mouse pad pages.

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