REPORT: State of the Union for Ecommerce Page Speed & Web Performance (Summer 2015)

In the hyper-accelerated world of technology, the modern consumer is bombarded with near-daily news of technological breakthroughs, OS updates, device refreshes and breakneck broadband speeds. With this all comes a reinforcement of expectations for modern webpages to deliver dynamic, rich content on par with high-definition cable programming, delivered just as fast as a user would change a channel from one HD broadcast to another.

However, the top ecommerce sites often place page speed at a lower priority than content and visual appeal. The result? Page bloat, with large, complex web pages loaded with resources which all have to load in some sort of order. There seems to be an implied belief that users will wait through the entirety of a page’s loading process to get to the goodies.

Unfortunately, studies have shown repeatedly that they won’t. As we’ve discussed before, users expect pages to load in just three seconds – or less – and they will abandon a website, no matter how visually striking, if it doesn’t meet that expectation.

Our latest research, conducted for our Summer State of the Union report, takes a no-nonsense look at the ecommerce sites users visit most to ask the question: Is today’s ecommerce experience matching the expectations of today’s users?


As we’ve done since 2010, we measured and analyzed the performance of the top online retailers, as ranked by, looking at key web page metrics from load time to TTI, page size/composition and the adoption of performance best practices. We utilized widely-available tools, including and, to obtain real-world snapshots of these pages’ metrics (as well as for web pages in general) and to evaluate their change from quarter-to-quarter and year-to-year. Our findings are detailed in our quarterly “state of the union” reports, some of which you can find here.

The performance of the top 100 ecommerce sites offers a revealing look at what’s going on behind the screen. Here are some of our findings:

1. The median top 100 ecommerce home page takes 5.5 seconds to render feature content.

While users expect to be served a full page in under three seconds, the median top 100 ecommerce home page renders its primary content 2.5 seconds later, and isn’t fully loaded until 15 seconds have elapsed. This is well outside of the three-second target.

  • Just 12% of the top 100 ecommerce sites rendered feature content within the three-second window.
  • Fourteen percent took 10 or more seconds just to be become interactive.
  • For 3% of the top 100 sites, it took 20 seconds or longer to become interactive.
  • Sixteen percent took over 20 seconds to fully load, with four of those sites taking over 30 seconds to do so.

This should concern site owners, since research has shown for some time that that :
57% of consumers will abandon a page that takes longer than 3 seconds to load.

2. The median page has increased in size by 13.59% in one year

Our Summer 2014 research showed the top 100 ecommerce site had a median size of 1677 KB, with 100 resources. That number has now grown to 1905 KB, with 169.4 resources – a marked increase from just one year ago.

Each page resource makes an individual round trip from the user’s browser, and each round trip can take 65-145 milliseconds (or more) for desktop browsers – numbers that add up quickly when a typical page contains more than 100 resources. At over 160 resources, the median page has quite a bit of round trip time baked in.

Remember: page size and complexity typically correlate to slower load times. We found a few instances where some resources to 20-30 seconds to load. Yes, seconds.

3. Forty-eight percent of the top 100 retail sites fail to compress images

Image compression is a core performance technique that minimizes the size (in bytes) of a graphics file without degrading the quality of the image to an unacceptable level. Compressing image files lightens a web page’s overall payload. Fewer bytes mean reduced bandwidth and faster pages.

Of an average page’s total weight, 60% is composed of images, which should make them a prime target for optimization. However, 48% of the sites we tested failed to compress images, and their load times generally suffered for it.

Only 3% earned an “A” ranking from for image compression, with the rest falling in the middle.

Here’s the spread, compared with our findings from our testing for our Spring 2015 report:

Summer 2015 Spring 2015
A – 3% A – 10%
B – 8% B – 10%
C – 13% C – 15%
D – 13% D – 13%
F – 48% F – 43%
N/A – 15% N/A – 9%

Major Consequences for Slow Ecommerce Sites

The consequences can be huge for sites succumbing to their mass, with 57% of visitors poised to bounce after the three second threshold.

Assuming your site:

  • averages 100,000 visitors per day
  • with a 2% conversion rate (a common conversion rate for ecommerce sites is ≈2%)
  • and those conversions average $54 each (90% of ecommerce shoppers spend an average of $54 per order)2

You would ideally be looking at $108,000 in daily revenue. But if 57% of visitors leave, they take those potential dollars with them to the tune of $61,560 daily, or $22,469,400 annually. Here’s the formula, where x = visitors and y = average revenue per customer, multiplied by 365 days:

(.57x)(.02)(y)365 = $Lost Revenue$

Considering this, the potential costs associated with image optimization seem insignificant in comparison.

1PhoCusWright, Consumer Response to Travel Site Performance, June 2010

2RJMetrics, 2014 Ecommerce Benchmark Report, 2014


Ecommerce site owners are striving to give their customers the content they want, and most – but not all – are sacrificing performance and revenue in the battle of “pretty vs. fast.” These top online retailers are responding to customer demands for content but are still discounting the importance of user experience in buying decisions, with potentially serious consequences, as outlined above.

The good news is there are significant opportunities for every site to optimize pages and fine-tune performance.

While page growth and complexity present critical web performance challenges, addressing these issues smartly with the proper optimization and automation tools can finesse significant site performance gains and keep users engaged.

Get the full report: State of the Union: Ecommerce Page Speed & Web Performance

Matt Young

As a technology evangelist and writer for Radware, Matt Young delivers research and articles to the application delivery and web performance community. Before joining Radware, Matt was a top blogger for BlackBerry and he also served as the Web Editor for Avaya and as a freelance technology writer in the Greater Bay Area. Matt has a Journalism degree from San Jose State University.

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