EC Site Speed Rankings August 2025: Top 270 Sites Analyzed and Insights Shared

EC Site Speed Rankings August 2025

In an era where digital presence is crucial, Gaprise Co., Ltd., a leading SaaS trading company based in Chiyoda, Tokyo, has just released the latest rankings of e-commerce site loading speeds as of August 2025. This evaluation sheds light on how vital site speed is in enhancing user experience and improving overall business performance.

Overview of the Research

1. Research Period

Data collected in August 2025.

2. Research Organization

Gaprise conducted the investigation.

3. Target Sites

Among the top 300 domestic e-commerce companies reported in the 83rd Mail Order Sales Rankings by the Mail Order Newspaper, the evaluation focused on sites with monthly traffic exceeding 100,000.

4. Methodology

The data was gathered utilizing Google Chrome's User Experience Report dataset. The research conducted a comparative analysis of the Largest Contentful Paint (LCP) metric for mobile devices over a 4G network at the domain level for each site.

For more information on LCP, visit Google's Developer Page.

LCP Explained

LCP stands for Largest Contentful Paint, one of Google’s Core Web Vitals. It measures the load time for the main content of a webpage, usually the largest image or headline text, occurring after the page load. A smaller LCP value indicates that the critical content loads quickly, improving user perceptions of speed. Google benchmarks the LCP metric with a target of displaying critical content within 2.5 seconds for a good user experience. In contrast, loading times exceeding four seconds yield low user satisfaction. A case study from Renault shows LCP improvements can further enhance the loading time to less than one second.

For Renault's case, see Web.dev Case Studies.

Insights from the Rankings (Top 10)

Breaking the One Second Barrier

A notable observation from the research is that all top 10 sites achieved an LCP of less than 1.2 seconds. Leading the rankings is Murauchi.com, followed by Amiami Online Shop and BAYCREW’S STORE, all demonstrating exceptional loading speeds.

Overall Performance

Of the 270 sites evaluated, around 72.9% (197 sites) achieved LCP under 2.5 seconds. This statistic indicates that many e-commerce platforms are recognizing the importance of loading speed and are actively pursuing enhancements in this area.

Stability Among Top Performers

The first-place holder, Murauchi.com, retained its position from the previous month, as did the sixth-placed Tsutaya Books. This stability among the top performers suggests that improving load speed is an ongoing challenge that requires persistent efforts rather than a one-time initiative.

Core Web Vitals: INP Excellence Among Top 5 Companies

The top 5 companies remain unchanged, indicating their sustained commitment to high interaction performance, which provides users with a hassle-free experience.

Interaction to Next Paint (INP) measures a web page's responsiveness to user inputs. When analyzed together with LCP, it allows for a comprehensive evaluation of site performance. Businesses seeking to enhance their web performance should integrate INP, LCP, and other Core Web Vitals metrics for an effective improvement strategy.

Contributing Factors to Score Improvement

Companies are achieving score enhancements through the following measures:

- Optimizing JavaScript execution
- Streamlining event handlers
- Enhancing rendering performance

This highlights the ongoing importance of continuous improvement and the adoption of new technologies beyond just LCP.

Accessing Additional Data

For detailed information on the top 270 sites and improvement case studies, visit our media outlet, MarTechLab.

About Gaprise

Gaprise continues to support various web performance improvement projects. As per Gartner Japan's projections, Japan's enterprise IT spending is anticipated to increase by 4.7% in 2023 compared to 2022, reaching ¥28.5 trillion, with expectations to surpass ¥30 trillion by 2025. The SaaS market, currently at ¥1.1 trillion, represents less than 4% and holds great growth potential.

Since its inception in 2012, Gaprise has aimed to differentiate itself by continuously discovering and proposing innovative technologies from around the world, forging robust alliances with enterprises that have seen significant funding successes or high growth prospects.

Moreover, following the discontinuation of Google Optimize in 2023, Gaprise will exclusively offer three recommended A/B testing tools and in February 2024, plans to introduce several site speed improvement tools. This approach allows for a diverse range of options tailored to client needs.

Through the integration of advanced technologies and consulting, Gaprise addresses various client challenges, from market analysis and online visibility to enhancing site user experiences, content management, project management, and AI technology, driving business growth.