Google Rolls Out Mobile-First Indexing – March 2018 SEO Update

After a year and a half of tests, Google has begun migrating sites that follow best practices to the mobile-first index.

What is Google changing?

Google is moving from using the desktop version of the content on any webpage to crawl, index and rank websites and pages.

Google will continue to have a single index used to serve search results.

The mobile-first index is now the main index, and the only index. There is not a separate index for mobile and desktop searches.

Why is Google changing to a mobile-first index?

However, now we are in a mobile-first world where people do a lot more searching on mobile devices, this isn’t the best way forward.

Now that Google is using the mobile version for rankings, Google is better helping the largest portion of their audience: searchers on mobile devices.

This better improves the mobile experience for searchers, and help them find what they are looking for more efficiently and simply.

How do I know if I’m migrating to mobile-first indexing?

Google is notifying sites via Search Console is they are migrating to mobile-first indexing.

If this is the case, then you will see an increase in the crawl rate from the Smartphone Googlebot.

On top of this, Google will begin showing the mobile version of pages in the Search results, and Google cached pages.

What if I’m not in the mobile-first index yet?

No need to be concerned. Google is using mobile-first indexing to gather content, rather than how it is ranked.

If content is gathered via a mobile-first index, it does not have an advantage in the rankings over mobile content gathered via the mobile-first index, or even desktop content.

If your site still only has desktop content, then you will still be indexed, though it’s worth moving over to a mobile-friendly website as soon as possible. Not only will you be providing a better experience to users, but it’s likely to become a bigger part of how Google indexes and ranks websites.

Google has been measuring mobile-friendliness since 2015, and evaluates all content to determine how mobile-friendly it may be.

From July 2018, Google will be penalising any content that loads slowly in the rankings, and so this will inevitably come down to mobile-friendliness. Mobile-friendly websites tend to be quicker, and so will perform better in the search results from summer 2018.


Google’s official recap is as follows:

  • Mobile-indexing is rolling out more broadly. Being indexed this way has no ranking advantage and operates independently from our mobile-friendly assessment.
  • Having mobile-friendly content is still helpful for those looking at ways to perform better in mobile search results.
  • Having fast-loading content is still helpful for those looking at ways to perform better for mobile and desktop users.
  • As always, ranking uses many factors. We may show content to users that’s not mobile-friendly or that is slow loading if our many other signals determine it is the most relevant content to show.