New E-Commerce Benchmark Proves the Impact of Site Speed on Conversion and Customer Experience

From first touch through conversion, retailers have carefully curated the entire online shopping experience to win consumers. However, far too often, brands overlook the foundation of that experience: site speed and performance. Until now, the impact of site speed was largely unknown. Does it really improve site key performance indicators? And if so, by how much?

Introducing the Site Speed Standard Benchmark Data

The Site Speed Standard, a section of the new e-commerce SpeedHub, is an easy-to-use, dynamic, and interactive benchmark data set for online brands to definitively prove the impact of page load speed on conversion and shopper experience.

Unlike older data used to benchmark e-commerce site speed and performance gathered by industry giants like Amazon.com and Walmart, this data was collected in April 2021 and provides insightful, relevant and fresh data from over 200 e-commerce sites across a wide range of brand sizes.

The Site Speed Standard breaks down the data into three main categories, each with its own data-driven set of key findings:

• Session Performance: Every session leads to an outcome. Speed has a significant impact on that outcome — will the shopper buy, browse or bounce?
• Shopper Journey: Combining pages into the complete shopper journey compounds the need for speed.
• Page Performance: Engagement is the key to the best shopping experiences that ultimately convert. Having a feature-rich site is very important, and one thing for certain is the faster the pages load, the more engagement you get.

Proof That Every Second Counts

Why is site speed so important? Faster sites provide a chance for brands to connect shoppers with their products while decreasing bounce rate and increasing conversion rate. The Site Speed Standard benchmarking data proves that page load time has a direct impact on conversion and bounce rate, and reveals what happens with every second brands can shave off page load time:

• Conversion rates increase by 5.7 percent on mobile and 3.3 percent on desktop.
• Bounce rates reduce by 12.2 percent across the board.
• Page views increase by .38 pages on mobile and .52 pages on desktop.

It should be no surprise that as page load times slow, conversion rates fall. Comparing the extremes of page load time averages shows a near-perfect negative correlation; the fastest load times see double the conversion rates, and half the bounce rate. So, what’s the number to beat when it comes to e-commerce page load times?

The Site Speed Standard benchmark data shows an interesting symmetry pivot on the four-second page load time average: sessions that beat four seconds capture 59 percent of conversions, while sessions that trail four seconds deliver a near-identical 58 percent … of bounces!

To “Cart or Not"?

The typical buyer journey is heavily concentrated to two page types: the product detail page (PDP) and the category page. These page types represent the “cart-or-not moments,” as shoppers are most intimately connected to the products on these pages. The Site Speed Standard shows just how much brands can benefit from optimizing these pages for speed and performance. According to the findings, an optimized buyer session completes (successfully with a purchase) before an unoptimized session even clicks into checkout!

Sounding the Bell on Heavyweight vs. Lightweight Sites

Engagement is the key to the best shopping experiences that ultimately convert, according to the Site Speed Standard. Having a feature-rich or “heavyweight” site is very important, and one thing for certain is that faster loading pages result in better shopper engagement. Unfortunately, many brands choose to cut down on third-party features and other site elements that shoppers enjoy in order to maintain a faster “lightweight” site. Yes, the site is faster, but the shopper experience takes a hit due to a lack of functionality.

Enter the Champ: Optimized Heavyweight Sites 

Heavy, feature-rich sites are engaging due to all the images and technologies that make incredible shopper experiences. Here, the strength of heavyweight sites and the speed of lightweight pages are combined for an optimal shopping experience. Here are some findings from the data provided by the Site Speed Standard:

• Sites with the heaviest page weights take 1.1 seconds, or 28 percent, longer to load compared to the lightest-weight sites, about 1.1 seconds more.
• When optimized, heavyweight sites on desktop are one full second faster than the lightest unoptimized (19 percent faster). Remember, we already explored the value of one second!
• When optimized, heavyweight sites are two seconds faster on mobile than the non-optimized version.

The recently launched E-Commerce SpeedHub is a one-stop learning center for everything e-commerce professionals need to know about site speed and performance. Powered by industry data from over 1,500 e-commerce sites, this hub features:

• Third-Party Benchmark Data: performance data on 500-plus third-party technologies.
• Site Speed Standard Benchmark measures the experience impact of site speed and performance, drawing on the shopping activity of more than 25 billion page views across 200 leading retailers' websites.
• Trending Topics: insights into the latest industry trends.
• Glossary: a single source of truth for all site speed terminology.

Rick Kenney is the managing director of Leading Lights, a company that helps SaaS companies create their own benchmarks from your platform data.