One image can destroy mobile web performance

Office Depot removed a heavy image and shot up 18 spots on a mobile index.

Bill Siwicki

A picture can say a thousand words. But if it weighs 244 kilobytes, it can wreak havoc with the performance of a mobile commerce web site.

Office Depot Inc. found this out the hard way. It had been running on its m-commerce site a promotional banner that weighed 244 kilobytes (see picture, right), says mobile and web performance management firm Keynote. To put that into perspective, Keynote says retailers seeking a page load time of 2-3 seconds should restrict a page to around 50 kilobytes in size. That’s 50 kilobytes for the entire page, not just one image.

The office supplies merchant removed the troublesome image last week and subsequently shot up 18 spots on the Keynote Mobile Commerce Performance Index. For the week ending May 12, its m-commerce site home page load time was 6.38 seconds and its site availability or success rate was 99.68%. Weighting and then combining load time and success rate earned Office Depot an index score of 937 out of 1,000, putting it in the No. 1 position. For the week ending May 5, the retailer’s load time was 6.06 seconds but its success rate was only 98.35%, earning it a score of 742 and position No. 19.

“Sears continues to be the fastest -loading site, requiring just over two seconds to load its tiny, 12-kilobyte home page. But it was nudged from first place by Office Depot’s better availability numbers,” says Keynote web and mobile performance expert Joe Flake. “Office Depot picked up performance improvement after removing the oversized promotional image. Using an oversized image is an easy mistake to make on any web site. This can be a minor bump for a large desktop-oriented page with a fast network connection, but can be disastrous for a small mobile site with an over-the-air cellular connection.”

Office Depot did not respond to a request for comment.

Sears Holdings Corp. came in second with a load time of 2.15 seconds and a success rate of 99.36% for a score of 935. Amazon.com Inc. came in third with a load time of 6.74 seconds and a success rate of 99.68% for a score of 932.

Office Depot is No. 65 in the Internet Retailer Mobile 400, Sears is No. 29 and Amazon is No. 1.

The index average load time was 9.64 seconds, the average success rate was 99.12% and the average score was 775.

Click here and then click on Keynote Mobile Commerce Performance Index Part 1 and Part 2 to see this week’s complete results for all 30 retailers on the index.

Keynote Systems measures 30 representative m-commerce sites exclusively for Internet Retailer. The sites include merchants in multiple categories and channels, and of multiple sizes, ranging from such giants as Amazon.com Inc. to midsized retailers like Toolfetch.com LLC. Keynote tests the sites in the index every hour Monday through Sunday from 8 a.m. through midnight Eastern time, emulating three different smartphones on three different wireless networks: Apple Inc.’s iPhone 4 on AT&T, the HTC Evo on Sprint and the Droid X on Verizon. The HTC Evo and the Droid X run Google Inc.’s Android operating system. Keynote runs the tests in New York and San Francisco.

Keynote combines a site’s load time and success rate, equally weighted, into a single score. Given that both performance and availability are important, the score reflects the overall quality of the home page; a higher score indicates better performance. Scores also reflect how close sites are to each other in overall quality. The index average score is the midpoint among all the sites’ scores.

Keynote is ranked No. 2 among web performance monitoring firms in Internet Retailer’s Leading Vendors to the Top 1000 E-retailers guide.


images, Keynote, m-commerce, m-commerce site, m-commerce site performance, Mobile, mobile commerce, Office Depot, Office Depot Inc., performance