Does speed & usability of a site affect SEO?

Posted by Richard Denver on 05 Jul 2021

Speed and usability seo

As some point you have opened a website to find it takes forever to render. It's a reminder of the good all days of Windows95. The days where your morning ritual involved turning on the computer, make a coffee and return just in time to see the operating system ready for a days work. Thank goodness those days are behind us! However unlike the 1990’s, people in the 2020’s are less patient and require their information on the move. So it's no surprise that frustratingly slow websites are considered a poor user experience.

For decades Google has been very secretive about their algorithm they use to rank websites. The algorithm has been unavailable to SEO specialists across the globe forcing specialist and SEO business’ alike to run tests to figure out what improves a websites Google page ranking.

In recent years however Google has sent a clear message to the digital industry, speed and usability are a major factor in the ranking score of a website. This was one of the first time’s Google was transparent about specific area’s that SEO experts and developers needed to focus on. To assist the digital industry Google introduced an array of open source tool, which included Google Lighthouse, PageSpeed Insights and AMP.

Lighthouse, along with PageSpeed Insights and AMP, are part of a push by Google to get website owners to improve their user experience, especially on mobile devices. Google has given AMP pages preference in the Google News Top Stories carousel on mobile devices, and they have made speed a ranking factor for mobile searches. These actions have forced SEO specialists and web developers to take page performance more seriously.

With each new version of lighthouse new changes are introduced affecting a websites score. From Lighthouse version 5 to versions 6 we have seen the introduction of:

  • Largest contentful paint,
  • Total blocking time, and
  • Cumulative layout shift.

Hence it is important to run regular tests on the latest version of lighthouse to determine where Google is now focusing it’s attention. The way to look at it is Lighthouse offers you a transparent view of what Google is focused on and what they think is important. It would be wise to consider the new shift in metrics and calculations, and to update how your site performs. If you don’t, it will end up costing you visibility in search results.

Traditional vs. Responsive websites

Usability is not constrained to the appearance of the website but includes how the website renders on today's devices. In the early years of web development it was relatively easy to develop a website for a desktop browser, as long as you overlook the IE and Netscape browser wars. The screen the user was using for the most part was relatively predictable and the same size for some years.

In 2007 this all changed with the introduction of the iPhone and in the proceeding years we saw numerous phone manufactures focus on developing similar phones, allowing the masses to access the web anywhere. Yet another game changer for developers came in 2010 with the introduction of the iPad. Since then we have seen hundreds of devices hit the market with a multitude of screen sizes and become know as the Internet of things (IoT).

In 2010 Ethan Marcotte coined the phrase responsive design. An idea that digital designers and developers should respond to the users behaviour and environment based on the screen size, platform and screen orientation.

With hundreds of screens sizes on the market, developers were forced to transitioning to responsive design. Today thanks to our friends at statcounter, we can see just how many screens sizes you need to cater for and how little difference their is from a usage perspective.

Source: StatCounter Global Stats - Screen Resolution Market Share

Companies initially attempted to solve this problem by developing apps for both Android and Apple and a mobile website for the remaining devices under a subdomain like It’s not surprising in recent years that companies started to abandon this idea as the overall cost of managing and updating multiple apps as well as multiple websites has become cost prohibitive. Today the focus has sifted to a mobile first philosophy. To assist developers plenty of great frameworks like bootstrap have made light work of developing content for all screen sizes. With the introduction of Content Distribution Networks (CDNs) website can present their content quickly regardless of where the user as the device retrieves content from the nearest CDN server.

In finishing with the introduction of more screens to come in cars, via interactive advertising and on new mobile devices it is no surprise that Google has sent a clear message to the digital industry, “clean up and improve your sites speed and usability or expect to be dropped down websites search rankings.