On average, retailers have 85 third-party integrations on their site. Personalization vendors slow down e-commerce sites the most, a new study finds.

The average retail website uses dozens of third-party technologies to power its e-commerce operations. While those integrations enable merchants to feature reviews, recommendations and advertisements on their site, as well as other engaging experiences, they may also be hindering the performance of those sites, according to performance optimization vendor Yottaa’s recently released report, “2018 E-commerce Third Party Technology Index.

And the potential for vendor integration-related problems is growing as online retailers’ use of vendors is rapidly increasing. Within Yottaa’s client roster, the average number of third parties that retailers used grew 129.7% between 2016 and this year. In 2016, the average Yottaa client had 37 vendors tools on its site, according to Yottaa’s client data. That number jumped 62.2% last year to 60 in 2017 and 41.7% this year to 85. Those numbers may skew high because of its large retailer customer base, a Yottaa spokesman says. Regardless of the specific figures, the trend line remains; a recent Retail Systems Research study of 80 retailers found that the average number of third parties is ranged between 40 and 60.

That growth reflects an industry-wide approach to technology. 65.5% of online retailers said they would use a vendor to implement a new technology versus the 34.5% who said they would build the technology in house, according to an Internet Retailer survey of 183 e-commerce executives, which was featured in Internet Retailer’s 2019 Leading Vendors to the Top 1000.

The top 20 third-party vendors that Yottaa’s clients use are:


Google also topped the list in the Leading Vendors to the Top 1000 for the most Top 1000 clients that used it for online advertising, at 441 retailers. Criteo was the No. 2 advertising technology vendor used with 211 retailer clients in the Top 1000.

But as merchants add more vendor integrations to their sites and apps, they’re increasingly the likelihood that their site performance will suffer. For example, a site with 40-85 vendor integrations, however, means a page would require 300 calls to more than 100 servers to load. Yottaa cataloged which vendors take the longest to load on average, and categorized them by type. These types of technology take longer than one second to load, which extends the time a shopper can interact with the site.

The more database queries, server calls, download configurations and content modifications required to serve the content, the more likely the page load time will slow.

The top five vendor categories that slow down e-commerce sites the most, such as taking one second or longer to load are:

  1. Personalization
  2. Tag management
  3. Advertising technology
  4. Social media
  5. Customer reviews


Within each of these categories, certain vendors are better than others in terms of not causing the site to slow down. Impact on load time varies by vendor for several reasons, such as how it was integrated into the site, if it was hard coded into the source code or not, how complicated the design of the feature is and how many calls to the server it requires, says Yottaa’s chief technology officer Bob Buffone. The report breaks it down by each vendor.

The Yottaa report is based on data from more than 1,000 e-commerce sites that use its services. Yottaa defines third parties as cloud-based technologies that are typically inserted as lines of JavaScript that transfer data and content between the vendor’s servers and the shopper’s browser.