Conversion Rate and Bounce Rate by Average Session Page Loads

As page load slows, conversion rate falls. 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 rates. *Mobile Conversion rate for average page loads under 2.5 seconds is artificially low due to the impact of bots on sessions.

Session Depth by Average Session Page Loads

Speed is also a strong predictor of session depth. Shoppers experiencing fast page loads consume more than twice the number of pages as those waiting for slow pages, and deeper visits are more likely to convert.

Average Page Load by Session Outcomes

The drag of slow page load has a clear impact on the shopper; bouncers see page loads that are nearly 50% slower than buyers or browsers. As average session page loads reach 6 seconds, bounce becomes increasingly likely. And, while session load times appear to be similar between buyers and browsers… (continue reading)

Average Session Depth by Session Outcome

(continued) … buyers consume far more pages than browsers, and those extra pages are — as noted later — dominated by product detail and category page types.

Beat 4 Seconds

An interesting symmetry pivots on the four-second page load time average: sessions that beat four seconds capture 59% of conversions, while sessions that trail four seconds deliver a near-identical 58% … of bounces.

Session Depth for the typical Buyer Journey

Anatomy of the Buyer Journey

The typical buyer journey is heavily concentrated to two page types: the product detail page and category page. These page types represent the cart-or-not moments, as shoppers are most intimately connected to a product.

The Sum of the Buyer Journey

Stacking the full buyer journey together, the true benefit of performance optimization is on display. Shoppers experiencing optimized pages save 15 seconds of page load across the journey, a 21% faster experience. Put another way, an optimized buyer session completes before an unoptimized session even clicks into checkout.

Page Load Performance by Page Type

The most trafficked of all page types - the product detail page - shows the true benefit of performance optimization. When optimized, PDPs load 34% faster - saving 2 full seconds of page load time on desktop, and 1.8 seconds faster, or 32% on mobile.

Optimizing High-Resource Sites

Heavy, feature-rich sites are engaging due to all the images and technologies that make incredible shopper experiences. Here we see heavy sites have faster page load times than lightweight sites that have decided to cut out their rich features for quicker load times. The brands in the benchmark are able to achieve lightweight speed for even the heaviest of sites, eliminating the need to trade speed for strength.