Today estimates vary, but most studies conclude that consumers believe websites should load with little to no delay, with 57% of users abandoning a page if it doesn’t load in three seconds or less, while 67% of UK consumers will quit online purchases as a result.

Worse still, other studies have shown that every one second of delay causes a 7% decrease in conversions, leading to billions of dollars in lost revenue each year solely to slow websites.

Given the potential revenue loss that slow pages represent, the expectation is that page load time, or latency would be constantly improving. However, this isn’t the case – in the two years from 2010 to 2012, page load times across major sites increased by 48% and this number is growing. 

In fact, average page loads for large publisher and brand sites now exceed an average of three seconds. The problem is just as bad when using a mobile device. In fact, when we looked at popular mobile websites, we found an average page latency of 1.68 seconds in January, and this increased to 1.74 seconds in just one month.

When initially trying to optimise page speeds, companies focused on issues associated with delivering content, such as the size of the page or structure. While large pages – those with a lot of scrolling content or complex structures – were initially difficult to optimise, these early problems have largely been assessed and fixed.

This resulted in an average page load of eight seconds in 2002 becoming an average of two seconds in 2010.

But there is a separate, significant contributor to slow page loads that has little to do with the content or the size of the webpage: tags.

Companies implement tags for many reasons. Some are served to provide analytics or display social widgets or video elements, while others are used to make serving adverts possible.

In order for adverts to appear on publisher and ecommerce pages, a signal called a script or tag is embedded into the page. When a webpage is loaded, this element causes the browser to ping an outside server and retrieve the advert.

Sometimes several calls are made for one advert to a host of companies who may be bidding for that ad spot and thus creating a “chain” of calls from the page. Individually, these tags may not slow down a page, but taken in aggregate, especially when there are many of them, these elements can cause considerable delays.

The average website now hosts over 75 tracking elements per domain, up from only 25 in 2003. Over 20 elements per page on average equates to at least a two-second delay, often more. As elements increase, so does page load time.  

Due to the evolution of advertising technologies and analytics services, many publisher and ecommerce sites added these tags in a haphazard fashion over time and by multiple, disparate departments.

This produced several unintended results, all of which contribute to slow web pages.

  • The first is an inefficient tag structure, where calls are made to a single company multiple times, or several companies are allowed onto a page, yet perform the same function. Each of the excessive calls should be examined and removed when possible.
  • Second, the cumulative nature of adding tags can create long tag chains, where fast elements sit behind slower ones, forced to wait for their slower partners to appear on the page.
  • Lastly, as tag structure and volume is a relatively recent area of focus, many publishers and ecommerce sites do not have a particular person or group of individuals monitoring their placement and performance.  

Each of these technologies associated with a given tag provide a valuable service to the publisher. It is possible to have a fast website that takes advantage of tags so long as steps are taken to improve performance.

Companies need to take stock and investigate which elements are found across their pages. They then need to discover how each of these vendors came to their pages and any third-party tags they may be bringing with them.

Once these are known, publishers can then assign their improvement and control to a given department or individual to ensure that performance is upgraded and maintained.

If companies don’t get their websites in order and the problem becomes worse, experiencing the slow days of dial-up is a very real possibility indeed.

Image credit: kewl via Flickr