[2026 Latest] How Does the Rakuten Search Algorithm Work? Fundamentals of "Sales" and "Relevance" for Beginners

Understanding the "search algorithm" is essential for maximizing product exposure on Rakuten Ichiba. Especially for new staff members recently assigned to EC operations, it can be difficult to know where to start. Unlike general search engines such as Google, Rakuten's algorithm is heavily optimized for "maximizing sales within Rakuten Ichiba." Based on the latest trends as of 2026, this article provides a clear explanation of the mechanisms behind "sales performance" and "search relevance," which form the core of the algorithm.

1. Why "Sales" is the Top Priority of the Rakuten Algorithm

In the Rakuten search algorithm, the most influential factor is "recent sales performance." As a platform, Rakuten Ichiba aims to maximize the Gross Merchandise Value (GMV) of the entire mall by displaying products that users are most likely to purchase at the top of search results. Specifically, the sales amount, number of units sold, and conversion rate (CVR) over the past few days to weeks are the primary factors for scoring.

As the graph above indicates, sales performance is believed to account for approximately half of the ranking determination. What newcomers must understand first is that it's not just about keyword stuffing, but rather the perspective of "how to create a state where products actually sell." The effectiveness of strategies that leverage advertising (RPP) to forcibly drive traffic and generate initial sales performance is rooted in these algorithmic characteristics.

2. Fundamentals of Metadata Design that Determines Search Relevance

Regardless of your sales track record, if your product is deemed "irrelevant" to the user's search keywords, it will not appear in the search results. This is where "search relevance" becomes critical. Rakuten's system analyzes information such as product names, catchphrases, product descriptions, "All Product Directory IDs," and "Tag IDs" in a MECE (Mutually Exclusive and Collectively Exhaustive) manner to determine the degree of alignment with the user's search intent.

The beginning of the product name is particularly important. Since keywords placed further to the left tend to carry more weight, the basic approach is to design the structure as [Important Keywords] + [Product Name] + [Specs/Bonuses]. Furthermore, as of 2026, AI-driven semantic search (meaning-based understanding) has been enhanced, and synonyms and relevant contexts are now taken into account. For those just starting out, begin by thoroughly analyzing which keywords top-ranking competitors are using and in what order they are placing them.

3. User Experience and Latest Trends: The Focus for 2026

In the latest algorithms, "User Experience (UX)" metrics can no longer be ignored alongside simple sales figures. For example, dwell time after reaching a product page, scroll rates, and above all, "review quality and freshness" are prioritized. Even if sales increase in the short term, a string of low ratings due to shipping delays or product defects will lower the algorithm's "Store Evaluation Score," negatively impacting search rankings.

Furthermore, with smartphone users now accounting for over 90% of the market, mobile usability (UI/UX) indirectly impacts conversion rates and, consequently, search rankings. Beyond just technical SEO, creating a page where customers can make a purchase without hesitation—considering factors like font size in images and information delivery speed above the fold—is ultimately the fastest route to Rakuten SEO success.