Google’s Mobile First Indexing: What You Should Know


Google has been experimenting with mobile first indexing for a few months. This change will make the mobile version of a webpage the dominant ranking version. This will mean that the mobile version of a page will be shown to users before the desktop version.

Information from web pages is kept by Google in an index. An index is similar to a library where there are “books” that can be retrieved when the user issues a search query. Until recently, the desktop version of the page was the dominant ranking factor. The desktop version of a web page is the version that users see when they are on a desktop computer. Over the past decade, the number of mobile users has increased.

The number of mobile users will be over 50 percent soon. Google has shown increasing interest in mobile friendly search results, as a consequence. The “Mobilegeddon” algorithm update in 2015 gave more search visibility to sites that had a mobile friendly design. With desktop web pages being the dominant factor, it is easy to see how this would not help mobile users. As a result, Google has been testing a mobile first index. Read more to learn how this will change SEO and how you can prepare yourself for the change. 

The result of having reduced content on mobile page vs desktop sites without a mobile version

The difference between the desktop and mobile version can result in users not getting all of the information that you want them to. If there is less content on the mobile version compared to the desktop version, your website could lose rankings. For example, if you have pricing information on the desktop version compared to the mobile version, users would not be satisfied with the mobile version. Some small business owners may be wondering: What if I don’t have a mobile version? The answer is, Google will show users your desktop site instead. Desktop sites can be less mobile friendly. In order to provide a good user experience, you might want to make sure that you have a mobile version of your website available anyways.

The result of having a separate website for desktop and mobile vs responsive websites

There is one type of website design that this “mobile first” algorithm change will affect the most. Due to the design restrictions of mobile, some companies have one separate site for mobile and one for desktop. Websites that have two different versions: one for desktop and one for mobile would be affected by the change. Sites that serve the same version on both pages would be not be affected by the change. This type of design is typically responsive design, which Google recommends for an SEO friendly website. Responsive websites show users the same content regardless of what device they are viewing it on. 

Possible effects on technical SEO factors: Google Search Console, canonicals, page-speed, AMP, and structured data

There are some steps you can take to prepare yourself for the change. If you have a mobile site on a different domain, such as, make sure to verify it in Google Search Console. This will keep you notified of any issues on your mobile site. Sites that have the same version on desktop and mobile will not need to add their website again.

Canonical tags on your website will not need to be changed. Canonical tags tell a search engine which version to rank in comparison to a similar web page. Since mobile website versions will be the default, canonical tags are unnecessary.

PageSpeed is a factor that matters with desktop sites. If a website was too slow, this could affect search visibility. With mobile first indexing, the impact of PageSpeed has not been determined yet. For websites with AMP, there will be no effect. AMP is a simplified form of HTML which makes mobile pages run faster. The regular mobile version of the page will be considered the default unless a website has all AMP pages.

Possible effects on SEO on-page factors: H1s, title tags, hidden mobile content

H1s and title tags are optimized on desktop sites and considered a ranking factor. Mobile pages are typically optimized for user experience and not search engines. When Google releases its “mobile-first” update, mobile pages will need to be optimized for indexing and ranking. Title tags might be shortened on mobile screens, so it is important to keep this in mind when writing mobile title tags. It would be a good idea to add H1s to mobile pages too. 

Mobile content is commonly hidden by interstitials or separated into tabs. Interstitials are screens that the user has to exit out of before accessing the main content. Tabs are sections of the page that can be hidden and shown again. Google has confirmed that hiding content in tabs will not affect ranking. Interstitials might, however. Google has confirmed that it will begin penalizing mobile sites with “intrusive interstitials.”

Read more about intrusive interstitials.


For a long time, desktop web pages have been the dominant version shown to users. However, this has not been very helpful to mobile users. Google has been testing it’s new “mobile first” index for months and it will be released soon. From that point on, mobile pages will be the dominant version shown to users instead. With the number of mobile users increasing, small business owners are advised to make sure their website is optimized for these users. If you have less content on your mobile pages, you will want to change this because it will not be as useful to users.

An even better option to have responsive web design so users will see the same page regardless of what device they are viewing it on. There may be some effects on technical SEO. Small business owners should make sure that their mobile site is verified in Google Search Console and that they have good page speed. You will want to make sure your on-page factors are optimized as well. H1s and title tags have been ignored on mobile web pages, traditionally. You should make sure that these are optimized for mobile now. Title tags might need to be smaller due to the screen size, also. Interstitials are common on mobile sites, but with Google’s new index, it would be best to make sure that they are not disrupting the user experience. After reading this guide you should be prepared for Google’s “mobile first” index.

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