The short answer is that pages on an e-commerce site should load in one second or faster since site speed starts negatively impacting conversion rates when page load times exceed one second.
One of the first major companies to advocate for faster page load times was Walmart. In 2012, Chris Crocker, Walmart’s senior engineering manager responsible for site performance at the time, presented a study that showed how conversion rates sharply declined when pages took longer than one second to load.
Years before Crocker presented this data, there was talk that every 100ms of latency cost Amazon 1% of profit. Whether this is true or not, it’s still true that page load time has a direct impact on bounce rate and conversions. 2018 data from Google confirms this.
Even though one second is the magic number, the average page load time for the average e-commerce site is stuck between 3 to 5 seconds. To direct this issue, 7 of the 10 of the largest online retailers have switched to headless commerce.
Improving site speed
The best way to improve site speed is through headless commerce. This is when you stitch together microservices from various commerce software providers with APIs. By doing this, elements of pages can load asynchronously since they are not being delivered from a single server, as is often the case with traditional, monolithic e-commerce setups.
Teespring, an e-commerce site that sells t-shirts and other apparel, doubled conversions when it switched to a headless commerce setup. The distributed nature of the headless tech stack allows elements of its product pages, checkout pages, and other pages to load asynchronously, thereby helping pages load faster.
Site speed testing and monitoring
To test the current speed of your e-commerce site there are free tools you can use. These tools will quickly give you a baseline for the performance of your site. They also offer detailed suggestions for how you can improve site performance.
Since testing individual pages with these free tools is cumbersome, many online retailers have engineering teams that use performance monitoring tools like New Relic.