[Thorough Explanation of Rakuten Thumbnail Guidelines] MECE Operation Logic for CTR Maximization EC Managers Must Master

WRITTEN BY
Risa Watanabe

Risa Watanabe

Senior Consultant

Meets Consulting Inc.

In the Rakuten Market sales equation (Traffic × Conversion Rate × Average Order Value), the most important variable directly linked to traffic is the "product image (thumbnail)." However, Rakuten has a strict "Product Attribute Information (Product Image) Registration Guideline," and violating it carries fatal risks such as a drop in search rankings (SEO) and suspension of ad delivery. In this article, we explain everything from basic knowledge of the guidelines to strategic thinking methods for achieving both rule compliance and click-through rate (CTR) improvement.

A professional workspace showing a digital marketer analyzing Rakuten marketplace search results on a high-resolution monitor, focusing on product thumbnail optimization and compliance metrics.

1. Four Core Requirements of the Rakuten Thumbnail Guideline

The "first image" on Rakuten Market must adhere to the following four items in a MECE (Mutually Exclusive, Collectively Exhaustive) manner to maintain platform uniformity and visibility.

  • Definition of Background: Photo backgrounds or solid white backgrounds only. Gradients and complex decorative backgrounds are prohibited.
  • Complete Elimination of Borders: Even a 1px border enclosing the image is strictly prohibited.
  • Text Occupancy Rate: Within 20% of the image area. It is necessary to narrow down to important appeals.
  • Geometric Patterns & Logos: Restrictions on logo placement unrelated to the product and patterns that impede visibility.
A technical diagram illustrating the 20 percent text occupancy rule for Rakuten product images, showing a grid overlay and prohibited border examples to ensure marketplace compliance.

2. Technical Impact on SEO and Ad Performance

Guideline compliance is not mere etiquette; it directly affects scoring on the search algorithm. Especially in RPP ads (search-linked ads), images violating the rules cause rejection in reviews or restrictions on delivery volume. Clean images enhance Rakuten's AI image recognition accuracy and promote search exposure for appropriate related keywords.

3. MECE Creative Design to Maximize CTR

To achieve both "following the rules" and "selling," prioritizing information is indispensable.

  1. Benefit First: Set a high-resolution photo that evokes the usage scene as the main focus, rather than just the product alone.
  2. Compression of Catchcopy: Place specific hooks containing numbers such as "Rakuten No. 1" or "Point Up" within the 20% limit.
  3. Device Optimization (Responsive Perspective): Adopt a highly contrasting color scheme considering visibility when browsing on smartphones.
Comparison between desktop and mobile viewports for Rakuten search results, emphasizing the visual impact of high-contrast product photography and clean typography within small screens.

4. Trends After Guideline Compliance Seen Through Data

The following is comparative data on the average CTR (Click-Through Rate) in search results when switching from existing "information-overloaded images" to "guideline-compliant + design-optimized images." By eliminating visual noise, the speed of user decision-making improves.

Frequently Asked Questions

Q Q. Does the 20% rule also apply to the second and subsequent images?
A. Current guidelines only strictly limit the "first image." While the second image onwards can be structured like a Landing Page (LP), excessive editing can lead to brand damage, so a unified tone and manner are recommended.
Q Q. Is logo placement also included in the text occupancy rate?
A. Yes, it is included. You must fit everything, including brand logos and icons like "Free Shipping," within 20% of the entire image.

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Popular Topics

#Rakuten Operation #Thumbnail Optimization #Creative Strategy

Summary

Adhering to the Rakuten Thumbnail Guidelines is a survival strategy on the platform itself. After clearing the three major elements of background, borders, and text occupancy rate, how visually you can express "user benefits" will determine victory or defeat. Perform image improvements based on correct logic and aim to maximize traffic from search results.

Published: 2026/3/24

References

  • [1] Rakuten Market Store Operation Navi "Product Image Registration Guideline"
  • [2] Rakuten RMS "Regarding the Importance of Product Attribute Information"
Disclaimer: This article is for informational purposes only. Please be sure to check the latest Rakuten official information on the RMS dashboard. It does not guarantee specific results.