Optimizing Your Website for Google’s Mobile-first Index

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Key Points
  • The number of daily searches performed on a mobile device outpaces desktop searches.
  • Google is currently testing a mobile-first index to match the increased demand for mobile-friendly sites.
  • Webmasters can learn how mobile-friendly their site is by using Google’s Search Console and Developer Tools.

One of Google’s main goals is to improve the user experience for all searchers. With the announcement of a mobile-first index at the beginning of November, Google is making digital marketers, developers and analysts think big about the user experience of smaller screens.

On November 4th, Google announced it was beginning to test a mobile-first index, an index that looks at mobile content first when assessing rank, and defaults to desktop versions of a site when a mobile one is unavailable. Historically, Google’s algorithm assessed the desktop version of a site and prioritized that version in rankings, while also having a separate mobile index that gave mobile-friendly sites a moderate boost.

This shift should come as no surprise to many digital marketers since Google has been hinting at the possibility of a mobile-focused algorithm for some time. In 2015, the search giant announced that mobile daily searches had finally outpaced desktop. Additionally, a recent comScore report showed that digital growth is coming from mobile users, and, while many are considered multi-platform users, desktop is clearly a “secondary touch point” for most.

The mobile-first index isn’t the only mobile-focused test coming from Google’s camp: Accelerated Mobile Pages, or the AMP Project, is another test that aims to deliver content to users at lightning–fast speeds. The AMP Project is intended to help publishers deliver their content quickly to users by removing slow loading content, like third-party, interactive Javascript. However, if you have a desktop version of your site and you’re implementing AMP as your only mobile-friendly strategy, it’s important to note that Google will only index the desktop version of the site. It seems counter-intuitive that Google wouldn’t index mobile-friendly AMP pages, but SEO experts posit that the desktop version of the site is more complete than the AMP version, therefore Google will index the version of the site that provides users with more content.

So what does all of this mobile news mean for webmasters and digital marketers? Let’s explore:

Why is Google Testing a Mobile-first Index?

The answer is simple: if users are searching and interacting with mobile content more than ever, it’s important that Google’s search engine result pages (SERPs) and, subsequently, the websites it delivers to its users are optimized for mobile.

If you haven’t prioritized developing a mobile version of your site yet, don’t panic. Google will still crawl the desktop version of your site. Currently, Google is in the process of testing the mobile-first index, but even when the new algorithm is completely integrated, it doesn’t render your desktop site useless. Having a desktop site with a great user experience will continue to be as important as it is today.

Here are the CliffsNotes for digital marketers: if your website isn’t mobile-friendly when the mobile-first index is fully integrated, expect your site’s rankings to be affected.

Ultimately, as a digital marketer, remember Google’s goal is to return the best, most relevant results to their users and to provide an unmatched user experience – now, through a mobile lens primarily. To succeed as a digital marketer, be sure that your website is delivering a top-notch mobile-friendly user experience and content.

Discovering If Your Site is Mobile-friendly

Not sure if your website is mobile-friendly? There is a very simple test to determine if the user experience of your site is good or not:

Search your site on a smartphone.

Granted, mobile user experience (and user experience in general) is a bit subjective, but it’s easy to tell relatively quickly if your site looks and functions properly on a mobile device. Does your site load quickly? Can you scroll easily? Are clickable elements easily navigated with a finger? Is the text readable without zooming in? These are a few questions to ask yourself when analyzing your site on a smartphone.

Additionally, there are a few tools you can utilize to test your mobile-friendliness. First, use the robots.txt testing tool to verify that Google can access and crawl your mobile site. If Google cannot access your site, submit and verify your mobile site in Search Console. Additionally, use Chrome DevTools’ Device Mode to emulate what the SERPs and your site will look like across multiple devices.

If You Don’t Have a Mobile Site

Again, don’t panic if you don’t have a mobile version of your site. Google will still crawl and rank your site based on the desktop version if a mobile one doesn’t exist. However, speak to your development team about prioritizing the implementation of a responsive design site or a dynamic serving site. Google prefers the content of a site to be the same (or close to it) across mobile and desktop, so utilizing a responsive design or dynamic serving site will accomplish this goal. If you do develop a dynamic serving site, be sure to use the Vary HTTP header to signal your site changes depending on the user-agent to Google.

Optimizing Your Mobile Design and User Experience

Here is an introduction to a few technical elements to optimize with mobile-first in mind:

Helpful Tools

In addition to the tools already mentioned (your smartphone, Google, robots.txt testing tool, and DevTools’ Device Mode), the mobile usability report in Search Console is a very helpful report to consider because it delivers a report that shows how your entire site is performing in terms of being mobile-friendly.

Improve Load Speed

Frankly, mobile users are demanding. Many users are looking for a quick answer on the go, so if your page is taking longer than 2 seconds to load, you can almost guarantee the user will press the back button and choose a different result from the SERPs. Test your page load speed with the Google’s PageSpeed Insights tool and consider ways you can improve it. Another tool powered by PageSpeed Insights is ThinkWithGoogle’s Test My Site tool. It analyzes how mobile-friendly a specific page is, not the whole site, and presents an interactive report that shows you how to improve the page. The report can also be emailed to you.

When working to update your page speed, consider optimizing your images, removing unnecessary code, and reducing the number of redirects on your site. Both PageSpeed tools provide a more in-depth, technical report of other changes to make.

Update On-page Elements

The SERPs will be smaller on a mobile screen. Consider this when optimizing title tags, meta descriptions and adding structured data to your pages. Search on a smartphone for high-priority keywords and pay attention to the results Google returns for mobile and how the information is presented. Understanding how Google wants to display results for the keywords could give you clues on how to update your own information. Chrome’s DevTools’ Device Mode would be a helpful tool to use here.

Remove Intrusive Interstitials

Do lead generation popups load when a user arrives on your site? These popups, or interstitials, may be easy to close on desktop, but can be detrimental to a good user experience on mobile. Starting on January 10, 2017, Google will devalue a site if it utilizes intrusive interstitials or popups that interfere with the accessibility of the main content of the page on mobile (Google is looking at you, “No, I prefer to pay full price” popups).

However, since Google is currently testing a mobile-first index, it would be wise to update your lead generation strategy to be in line with the mobile interstitial algorithm update before it rolls out in January. With Google already prioritizing a site’s mobile experience with their mobile-first index, it’s not a stretch to consider that Google may penalize sites for intrusive interstitials ahead of the update integration.

Develop Mobile-friendly Content

The question “how does it look on mobile?” can no longer be asked at the end of a project. The mobile functionality of a website needs to be considered from the beginning of an idea through its implementation. Most mobile users are navigating their phones with one hand and in the vertical (or portrait) orientation, so scroll through your site in the same way to troubleshoot any potential user experience pitfalls.

Lastly, how does your content display on mobile? Because of the smaller screens, concision in your storytelling is paramount. Reorganizing your text may be the easiest part, but if your site visualizes data, displays maps or utilizes some other unique, interactive content module, you may need to get creative with your development and design team to think of new ways to display your content. A good rule of thumb is to use the K.I.S.S. method: keep it simple, stupid. The best ideas are usually the simplest ones and clear, easy to navigate content will continue to provide a positive user experience for your visitors.


Above all, improved user experience is the catalyst that dictates almost all of Google’s changes and iterations to their algorithm. As a digital marketer, make user experience the nucleus of all of your projects — on-page and off-page — for better rankings and results.