Google speed update, July 2018: The new mobile ranking factor

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Google speed update, July 2018: The new mobile ranking factor

Starting on 9th July 2018, Google began to consider how fast a web page loads when calculating its ranking in mobile search results.

Site speed has been a ranking factor for desktop results since 2010. This new algorithm update reflects changing search habits on the modern mobile-centric web. The “Speed Update” will affect all businesses which gain traffic and revenue from organic mobile Google results.

In this post, you’ll learn about the background, purpose and impact of the Google Speed Update. I’ll also provide practical advice for making your website faster. Read on for quick wins for an immediate speed boost, and game-changing opportunities to transform your mobile experience.

What is the Google speed algorithm update?

TL;DR: Beginning in July 2018, Google will consider the speed of a web page when determining its visibility in organic search results on mobile devices. It doesn’t matter which technologies you use to build your pages, so AMP does not bring an inherent advantage. Google may still serve a slow page if it is very relevant to the query – but, for the most competitive search terms, you’ll need to be fast to be first.

Three types of Google ranking factor

Google considers hundreds of factors when determining how a web page should rank in its organic search results. These factors are not public, and given Google’s machine learning capabilities, they may not even all be known. However, they can be broadly grouped into relevance, trust and performance:

  • Relevance considers how likely a web page is to fulfil a searcher’s intent. Our Technical SEO consultants optimise this for clients through on-page optimisation and mobile SEO.
  • Trust determines the likelihood that the web page is valid and verifiable. Our content marketing team increase trust by running digital marketing and PR campaigns to garner shares and links.
  • Performance assesses the quality of experience a user is likely to have on the page. Our UX and creative team use clean coding and delightful design to deliver slick experiences for our clients.

Page speed has been amongst the performance metrics used to calculate Google rankings since 2010. However, until now Google has only factored speed into its desktop search results. Now, Google has confirmed page speed will also influence mobile rankings from July 2018.

Which search results will change after the Google Speed Update?

In their announcement, Google confirmed the revised mobile algorithm will penalise the slowest pages for some search queries:

The “Speed Update,” as we’re calling it, will only affect pages that deliver the slowest experience to users and will only affect a small percentage of queries.

Our interpretation of Google’s post is that relevance and trust will still trump performance factors for most rankings. For example, a slow page will still rank when it is an excellent match for a query, or when it appears on an authoritative website.

Conversely, we expect the Speed Update to have the greatest impact on the slowest pages for well-searched, competitive keywords. Here, many faster pages also target the same search intent. Ecommerce retailers, take note!

In a nutshell: when relevance and trust are equal, performance – and so speed – will determine the top-ranked results.

Update: In a Google Webmasters Hangout video conference, John Mueller (Webmaster Trends Analyst at Google) stated site speed improvements will have an incremental benefit. Apparently, website owners will feel a cumulative gain from many small, positive changes.

It is unusual for Google to provide advance warning of an algorithm update. This tells us two things: the impact of the Speed Update will be substantial, and Google want businesses to spring into action and address the issues which it concerns.

Why is Google making speed a mobile ranking factor?

TL;DR: Speed is becoming a mobile ranking factor because Google serves more mobile results than desktop results. Smartphones are becoming faster, but web pages are becoming slower. This impedes mobile conversions and increases the barrier-to-entry.

How the mobile web has changed

The launch of the Apple iPhone in 2007 triggered a boom in smartphone usage and, consequently, steep growth in mobile web consumption. In the UK, the number of people accessing the web via mobile has increased from 36% in 2011 to 73% in 2017. In the US, about 6 out of 10 web searches originate from a mobile device.

Given these stats, you might think content creators would focus on delivering great mobile experiences. However, as smartphones have increased in processing power, content creators have targeted consumers with ever-more complex web pages, riddled with intrusive analytics. Since 2011, the size of an average mobile web page has bloated by 11 times to 1,561 kilobytes. This is equivalent to 700+ pages of text, or most of Harry Potter and the Order of the Phoenix. Meanwhile, the average number of HTTP requests (images, scripts, analytics, etc.) has grown from 17 to 77.

Fast devices, slow web pages & weak connections

Furthermore, although devices have become faster, connections remain flaky. Although superfast 5G is on the horizon, Google estimates 70% of global web users will browse at no more than 3G speeds by 2020. Ofcom analysis shows only 63% of the UK population can access the web away from home at 2 Mbit/s (one-third of the average 3G speed across the UK).

Even those lucky enough to browse over a stable 4G connection will suffer. The average mobile web page is 91% of the size of the average desktop web page. However, the average UK 4G connection is just 32% of the speed of the average fixed-line broadband connection. The equivalent statistic for 3G is just 13% – definitely unlucky for some! (Sources: latest Ofcom reports into mobile and fixed-line broadband.)

The consequence of weighty pages and weak connections is loss of speed. According to Google, the average load time of a mobile web page is a disappointing 15 seconds.

Just as businesses need traffic from Google to thrive, Google needs business websites to maintain users’ trust in their search results. 53% of mobile users will bounce from a web page after just three seconds spent loading. Users who have a negative experience on mobile are 62% less likely to purchase from a business in the future. By directing mobile users to a slow web page, Google becomes guilty by association.

Therefore, the Google Speed Update is rewarding web pages which make the effort to deliver a fast experience on mobile devices.

While this algorithm change will benefit Google (naturally), they are being cruel to be kind. Slow websites have higher bounce rates and lower conversion rates. A memorable statistic from 2012 revealed a one-second increase in Amazon’s load time would result in a $1.6bn reduction in their annual revenue.

Is the Google Speed Update related to mobile-first indexing?

TL;DR: Mobile-first indexing is a change to how Google crawls your website to find and record its contents. It is not linked to the Speed Update. However, a well-designed mobile site is likely to find both changes beneficial to their organic traffic.

What is mobile-first indexing?

You may also have heard of another 2018 Google update called “mobile-first indexing”. Whereas the Speed Update tweaks how Google calculates its rankings, mobile-first indexing changes what Google is ranking.

When you conduct a Google search, you are not actually searching the live web. Instead, you are searching static copies of everything Google has found the web and saved to its servers. This is called the ‘index’. Searching Google’s index is similar to using the index of an encyclopedia to go direct to a specific article, rather than flicking through each volume until you stumble upon the right page.

Ever since Google launched in 1998, they have built an index of the web as it appears on desktop computers. However, most people are now searching Google on mobile devices, looking for great mobile experiences. To reflect this change, Google is switching its index to reflect how websites appear on mobile instead of desktop. This affects all websites, no matter how they serve mobile users – for example, via responsive design or separate mobile pages.

When did it begin?

Mobile-first indexing is already underway for sites which Google considers ready to switch. Google is prioritising sites with a reasonable mobile experience which serve similar content to mobile and desktop users.

There is no direct connection between mobile-first indexing and the Google Speed Update. However, a fast mobile site will switch to mobile-first indexing sooner than a slow one, as well as being a beneficiary of the Speed Update.

How can I measure the speed of my website?

There are many browser-based tools which grade the speed of your website. These tools test your page speed, identify bottlenecks, and diagnose technical faults. This information empowers you, your developer and your SEO partner to make your website faster.

Our favourite site speed analysis tools are:

  • PageSpeed Insights.
    This official developers’ tool from Google compares your page’s speed to the rest of the web. It also scores your optimisation as a percentage, and identifies technical improvements to get closer to a 100% score. Top tip: if PageSpeed Insights recommends compressing images, minifying CSS and/or optimising JavaScript, scroll to the bottom of the page to download optimised versions of all such assets on your page. Google have also published guides to resolving the most common page speed issues, and we’ve embedded a video to help below.
  • Test My Site with Google.
    This jargon-free Google resource downloads your web page over a simulated 3G mobile connection. It then tells you not only your load time on mobile, but also what percentage of your potential traffic will bounce before hitting your landing page at all. You can also review your site speed against other sites in your vertical, ideal for analysis of competitive landing pages following the Speed Update.
  • WebPageTest.
    This is one of the longest-standing site speed analysis tools on the web. In fact, Test My Site with Google takes some of its performance data from WebPageTest. Designed for developers, it provides a granular review of how your page downloads. Ahead of the Speed Update, we recommend setting the test location to an Android or Apple device and your connect speed to “3G” to replicate the same testing conditions which Google will use.
  • Pingdom.
    Unlike WebPageTest, with Pingdom’s speed testing tool you cannot specify the browser and/or device type. As tests are run on a simulated desktop rather than mobile, this makes it less useful for Speed Update analysis. You can set the location, thought, which makes Pingdom a handy helper if you set up your site with a CDN (see below).
  • Google Chrome + Lighthouse.
    The most powerful page speed tool might just be the one you already have installed on your computer. While Chrome is a capable browser for the end user, it conceals a veritable Aladdin’s cave of development tools. Use findings from the Audits tab, which runs Google’s series of Lighthouse tests, for optimisation recommendations straight from the horse’s mouth.

Video: improve your Google PageSpeed scores

Here are a few words from Matt Gaunt at Google I/O on how to increase your Google PageSpeed Insights scores for desktop and mobile:

How can I make my website faster?

After running your web pages through the tools listed above, it’s likely you’ll find optimisation opportunities ahead of the Google Speed Update. Here are common ways to make your website faster, ordered from easiest to hardest to implement:

  • Minify your source code. Remove unnecessary characters from your HTML, CSS and JavaScript to reduce their overall number of bytes. There are plenty of online tools which strip whitespace and comments from your code. Furthermore, there are dedicated CSS minifiers which refactor your markup to set the same page styles with fewer rules and attributes. Rating: Easy.
  • Leverage server compression and caching. Similar to minification, you should use gzip compression to reduce the size of your web page source code by as much as 70%. You should also set a longer expiry time on files which don’t change often, such as images and external scripts. This won’t make them load faster in the first instance, but will encourage browsers to hold onto the files for longer before downloading them again. Rating: Easy.
  • Image optimisation. For bitmap images such as photographs, use appropriate compression and serve at the dimensions they’ll appear on the page to avoid slower rendering. Also, consider using the faster WebP file format (with JPG/PNG fallbacks for older browsers). For vector images such as logos and graphics, use SVGs where possible, and limit colour palettes on PNGs and GIFs. Rating: Tedious, but easy.
  • Content Delivery Network (CDN). Instead of serving all your files from a single server, distribute your static resources (images, CSS, scripts) on servers across the world. Then, detect each user’s whereabouts and deliver those resources from their nearest location. This decreases latency and increases page speed. Setting up a CDN via a third-party provider such as CloudFlare is easiest, but at an extra cost. Rating: Slightly harder.
  • Enable HTTP/2 and HSTS. HTTP is the protocol used to serve content on the web. The previous spec, HTTP 1.1, was formalised in 1997 before the days of a rich-media web. The new HTTP/2 spec enables intelligent communication between servers and browsers, plus simultaneous downloading of key resources, for reduced load times. Add on HSTS preloading to instruct popular browsers to always download your pages via HTTPS. This avoids the slight delay of server-side redirects. Rating: Slightly harder.
  • Optimise CSS & JavaScript delivery. While developing a website, it is often easiest to keep HTML, CSS and JavaScript in separate files. It can also be helpful to separate subsets of styles, or scripts with different purposes. Convenience for developers equals slowness for users. Dividing up files increases the number of required resources to build a page. Inline critical CSS and scripts, and combine external files where possible, to simplify browser rendering. Rating: Tricky and fiddly.
  • Accelerated Mobile Pages (AMP). While its current goal is to deliver great experiences on all devices, the ‘M’ in AMP reminds us Google launched the AMP Project to make the mobile web faster (by as much as 85%). To reap its benefits, rebuild your pages using a pared-down selection of HTML tags, with no more than 50 kilobytes of CSS and no custom JavaScript whatsoever. Combine AMP underpinnings with a Progressive Web App for a near-native app experience. Rating: Hard.
  • Improve your server set-up. While the above optimisations will make your website faster, they will amount to a drop in the ocean if your server is bogged down. If you use a managed hosting solution, ensure it is suitable for your needs. Consider upgrading from shared to dedicated hosting if your customers experience slowdowns and 500 errors. If you manage your own server hardware, monitor CPU status, RAM consumption, temperature and uptime via software such as New RelicRating: Hard, time-consuming, and often expensive!


Rather like Britain, web pages are in the midst of an obesity epidemic. The typical mobile web page – overladen with adverts and analytics – is nine-tenths of the size of a desktop web page, despite connections two-thirds slower than fixed-line broadband.

Google’s Speed Update is an algorithmic equivalent of the sugar tax. It is designed to penalise website owners whose lazy coding and excessive scripts are slowing down the mobile web. All of a sudden, Google have forced businesses to prioritise best practice improvements, no matter how much development resource they necessitate.

While it might seem like just another algorithmic inconvenience, the Google Speed Update is an opportunity to get ahead of your competitors. Invest today, and secure your mobile visibility for now and into the future.


If you’re worried about the impact the Speed Update could have on your business, then naturally RocketMill can help.

Our teams’ close collaboration delivers valuable insights and actionable recommendations. For example, our Data & Insight team can ensure Google Analytics is capturing the whole picture of your site performance. Then, our Technical SEO team will analyse this data to identify pages and templates where speed improvements are most likely to impact your bottom line. For more information, get in touch.