Everyone working in SEO knows that Google has a multitude of factors they use to determine the order of search engine results, and the majority of these ranking factors are based on either the content of the webpage or signs of authenticity or reputability. That was the case for the longest time, but since 2010, Google has made significant shifts towards a focus on usability, and the harbinger of this change was the inclusion of website speed to ranking factors.
The problem is, website speed and other usability issues aren’t exactly objectively defined. What exactly is a slow loading site? What is the cutoff? No one has gotten a definitive answer from Google, but in June Matt Cutts explicitly stated that slow loading sites, especially on mobile platforms will begin seeing search rank penalties soon.
Obviously these changes are good for searchers. Searchers want sites that load quickly, offer quality user experience, and deliver great content. And, the emphasis on speed is certainly highlighted on mobile platforms where on-the-go users are likely to go back to the results if the site takes too long for their liking. The issue we face as search optimization professionals is trying to figure out exactly what Google is measuring and how that information is being used.
Matt Peters from Moz decided to break through Google’s intentionally vague information to figure out exactly how site speed affects rankings with the help of Zoompf. They can’t explicitly disprove causation between site speed and rankings, due to the number of other algorithmic ranking factors that complicate the study. But, their results did show very little to no correlation between page load time and ranking.
I wouldn’t take this information as gospel, but it does suggest that loading time isn’t a huge consideration into long tail searches and doesn’t need to be worried about too much. If your site is loading quickly enough to please the people coming to it, your site will also likely pass Google’s expectations.