The state of e-commerce websites – Part 3: Product Pages

Now we are getting down to the nitty gritty of e-commerce websites. Once you are through the shop path you are at the point where you can really start to purchase things – The product page. Because there may be a variety of information about the product, zoomable views, additional images, personalization options and shopping functionality – These pages tend to have more scripts and so tend to be larger than other pages.

Now, we may not always be comparing like with like here. product pages on a site may have different capabilities, some may have video, some will have customer reviews (More on the 3rd parties providing these services later), some may have multiple product options and we have already mentioned alternate / zoomable views.

Items of note wile doing this post were:

  • Macys site was unavailable when I first tried it
  • PageSpeed does not like some pages e.g. at Crate & Barrel and Best Buy and so i could not get a PageSpeed score

Items of note in performance were

  • GAP – Similar number of page items to Amazon and a faster return visit time – Although, I am mainly looking at the Document complete point here. If we wait until document loaded they have had quite a bit more time and page weight, but still a good time to DOM complete and good postponement of processing. We’ll look at that in detail another time
  • Sephora again comes in with a high number of requests to get to DOM complete for subsequent requests
  • A good few pages took more than 10 seconds to get to DOM complete on our ADSL from Virginia test
  • Williams-Sonoma got a rather easy page with no video or other heavy pieces. Will re-run on a video page, however the cores on Y!Slow and PageSpeed are still good

The state of e-commerce websites – Part 2: Categories & Sub-categories

In this post I have collected the performance of the first category and then a further sub-category from the sites I am looking at.

I let webpagetest test run each test 10 times to get a better average – This is still not that scientific but hopefully will be a little more representative. At some point I will go back and do the same for the home pages.

Now we are off the home page, we should be getting into areas that more represent the architects and engineers work.

Some things to call out on the Category Pages are:

  1. Barnes and Noble first view time is nearly double that of everyone else – This appears to be caused by downloading nearly 40 JS and CSS files before getting to an image. Seriously, there are 36 javascript files and 12 CSS files called by this page. Also, the CSS and JS are intermingled so that they can’t even get the CSS to download in parallel.
  2. CB2 has the largest initial payload at ovr 1MB. The main component of this appears to bet the VisualCart.swf coming in at 493KCB2 - VisualCart.swf Size
  3. Crate & Barrel and Sephora come in with over 90 repeated requests when the category page is called for the 2nd time. This is nearly 3 times more than Amazon, which at 33 still has nearly 20 more requests than the next highest.
  4. Amazon and Sephora both have over 100K in requests for a subsequent download. This seems a little high, although it will take a little more research to identify what is being reloaded that is not being cached

The spreadsheet is embedded below.

The state of e-commerce websites – Part 1: Overview

A big disclaimer up front – I am currently working for Williams-Sonoma which includes the Pottery Barn family of websites and West Elm. It is part of my role to look at front end performance with particular reference to the javascript.

I was surprised to find how many e-commerce sites are based around the Bay Area. From Walmart.com in Brisbane to Macys and Bloomingdales downtown.

Performance is an important aspect for e-commerce sites and so I thought it might be interesting to look at a group of them and compare speed, page weight, third party scripts and potential performance improvements.

In looking at the websites I want to look at 1) The home page, 2) a category / sub-category page and 3) A product page.

My first task was to get a list of the sites I want to look at. As I am working for a company taht has retail stores and also an online presence I thought it would be interesting to look at sites with a similar background.  The ones I chose are Macy’s, Bloomingdales, Sephora, Walmart.com, Crate and Barrel, CB2, Gap and Barnes and Noble. I have also added Amazon.com as a pure internet business to see if that makes a difference.

I am going to use a variety of methods to examine the sites – Initially I’ll use webpagetest.org to get some initial stats and I will also get the grades Google’s Page Speed and Yahoo!s YSlow Firefox plugins

For this post I have just gathered some basic information on the home pages of these sites. Home pages are generally the first page a user sees. and first impressions are important. However, in general, they are not necessarily reflective of the rest of a site and so I think should be treated differently.


All webpagetest.org tests were carried out with the following params From: Dulles, VA – 1.5Mbps ADSL using IE7

Updated 5/15/2010: Added Best Buy so we have a 10th clicks and mortar store