Slow page speed: what to measure, how to measure, and how it’s affecting your ecommerce channel

A recent article on the Econsultancy blog discussed the issue of page load times getting slower with some helpful tips on what can be done to help speed things up.  

The article stimulates other questions that I thought it would be interesting to tackle in more depth. 

These include issues such as: 

• What should be specifically measured to determine a true sense of page load time? 
• What tools can be used to measure your pages? 
• What are slow page load times doing to your ecommerce channel?

What should be specifically measured to determine a true sense of page load time?

To understand what both new and existing consumers are facing when they are loading your pages, a few different scenarios should be undertaken when measuring page load speed times:  

• First view – how long do pages load the first time someone comes to your site. 
• Repeat view -  how long do pages load when someone comes back to your site.

Both are important, and both first and repeat view traffic types have high expectations.

For both first and repeat views, there are three specific metrics to measure: time to first byte, render start, and load time.

Time to first byte. The time to first byte measures the amount of time it takes for the servers (where your site is hosted) to react to the request of sending data (your content) to a browser (the browser of the individual who wishes to view your website).  

This determines if your server environment/infrastructure is truly responsive to the needs of your website.

Render start. The render start is a measure of time required for the first page element to appear on the browser. In other words, how long does it take for the individual to see something on their screen?  

Load time.  Load time is measured as the total time taken to load all elements of the page requested.

Once you have the above data for both first and repeat views there is one more scenario that needs testing - the above metrics under normal conditions, and conditions of stress (i.e. how does the website load content during campaign activity).

What tools can be used to measure your page load speeds? 

There are a quite a few options, but Webpagetest.org appears to be the most consistent in its data, and produces all the above metrics.   

What to do with this data?

Once you regain consciousness from the poor results, the reporting will indicate precisely what is slowing the pages down.  There is another very good article taking a technical view on what to do to increase the speed of loading pages.  

The most common reasons for slow loading pages is a mix of heavy images, heavy interactive page features (i.e. carousels on the home page) site build shortcuts from the dev team, and/or hosting environment not equipped to handle the traffic.  

For the purpose of context, have a look at Amazon's results:

First View:

• First Byte: 0.285 sec
• Render Start: 0.944 sec
• Load Time: 2.071 sec

Repeat View:  

• First Byte: 0.285 sec
• Render Start: 0.833 sec
• Load Time: 1.346 sec

What are slow page load times doing to your ecommerce channel?

Mobile users are impatient.  The issue of load time is no longer confined to your website displaying on a PC or laptop.  If it takes seven seconds to display your content on a PC what happens with your mobile site on a 3G network?  

A study was done by Keynote who surveyed over 5,000 people in the first half of 2012 to find 66% of respondents expected mobile sites to load in under four seconds. It can be assumed this expectation has risen since then.  

Google's support of page load times. While the purpose of this discussion is to recognise methods to solve slow page load times to improve the experience for consumers, it is worth noting a recent study showing a correlation between Google rankings and time to first byte.  

Over 2,000 websites had taken the above measures only to find those with a more robust back-end infrastructure achieved higher search rankings.  

The creators of the study had this to say about why they felt Google would use this metric: 

TTFB (time to first byte) is likely the quickest and easiest metric for Google to capture. Accurately measuring the various load times is also browser dependent and relies on its ability to load images and content. 

Using TTFB to determine the "performance" or "speed" could perhaps be explainable by the increased time and effort required to capture such data from the Google crawler. Not only is TTFB easy to calculate, but it is also a reasonable metric to gauge the performance of an entire site. 

Ever wonder why you are experiencing high bounce rates for highly targeted campaigns?  Many times marketers attribute high bounce rates to a high influx of traffic. That may be true, however, consideration of page load times under high stress is recommended.  

How does Google Analytics (GA) record a "bounce"?  If you have a situation where a page is taking seven seconds to load, but after the third second, the individual gives up and leaves, a "bounce" is ackowledged in GA.  If the tracking code is installed correctly (in your header), GA recognises the visit as a pageview and therefore a bounce.

You can have the most effective campaign running, however, slow page load times will stifle your ability acquire new business and stimulate repeat sales.

Get measuring... good luck.