The mobile commerce web site of Barnes & Noble tops the Keynote Mobile Commerce Performance Index for the week ending March 17. It has been ranked among the top three retailer sites every week on the 30-retailer Keynote index since November 2012. This is not an easy accomplishment, says Herman Ng, mobile performance evangelist at mobile and web performance management firm Keynote.
“In terms of its mobile page load success rate, Barnes & Noble has maintained a rate higher than 99% every week except one, when it slipped to 98.72%,” Ng says. “In terms of its mobile page load time, Barnes & Noble has maintained a time between four and six seconds except once, when it slipped to 6.04 seconds.”
For the week ending March 17, the m-commerce site home page of Barnes & Noble loaded on average in 4.76 seconds and did so completely and successfully 99.88% of the time. Weighting and then combining load time and success rate earns the merchant an index score of 948 out of 1,000.
A close examination of performance data over the last four months shows Barnes & Noble, No. 31 in the Internet Retailer Mobile 400, offers exceptional mobile web design, Ng says.
“They keep their mobile home page lean and mean with less than 30 kilobytes in total size, and the page has only one redirection, one JavaScript, two Cascading Style Sheets and three domain names in total,” Ng explains. “All page objects, including images, are hosted on the same domain. Except for one JavaScript and one CSS file, most objects are very lightweight—less than 6 kilobytes each. Overall, the only area where I believe they could do better is to use CSS sprites to transfer all their images together, which would require only one response over the network instead of many.”
A sprite is a web programming technique that enables multiple images to be saved as one, thus reducing the number of web server calls required, and as a result shaving time off of page loads.
Barnes & Noble did not respond to a request for comment.
Rounding out the top three, W.W. Grainger Inc. came in second with a load time of 3.84 seconds and a success rate of 99.66% for a score of 940. Amazon.com Inc. came in third with a load time of 6.33 seconds and a success rate of 99.77% for a score of 886.
The index average load time was 8.66 seconds, the average success rate was 99.16% and the average score was 729.
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.