As more and more searches are coming from mobile devices, Google is following suit to represent this shift and is creating a separate mobile index that will become the primary source for all search query results.

When will the mobile-first index roll out?

This is a difficult one. When asked back in March, Gary Illyes, Webmaster Trends Analyst at Google, hinted at an early 2018 release, however, we have already had confirmation that a number of sites have been tested on the mobile index in the wild for a number of weeks dating back to October 2017.

More recently, Google’s John Mueller gave a signal of an impending wider rollout when he offered up clear instructions on how to discover if a site has moved to the mobile-first index.

The mobile-first index appears to be a controlled iterative switch for most sites so it would be wise to follow the advice and inspect your log files regularly.

What will change with Google’s mobile-first index?

Currently Google has indexed your website based on a desktop user’s experience, taking into account only the desktop version of a website and the content within. With a mobile-first index, Google will switch this around to index and rank your website based on the content and information architecture of your mobile site as a primary view.

While Google’s Gary Illyes stated at the SMX West conference in March, that they would fully launch the mobile-first index when results are “quality neutral”, some sites with substantially different mobile experiences to their desktop sites may inevitably find issues with rankings.

How can you prepare?

If your website is designed responsively (or with a dynamic serving setup) and your primary content and mark-up is the same across mobile and desktop devices, you are already in good shape but if you fall outside of those parameters, you should consider making some changes to your site.

Google has given some specific recommendations to webmasters looking to prepare for the change in their official announcement, but there are some basic steps you can take to get your website ready:

1. Make sure your site is mobile friendly

With more than half of all web traffic coming from a mobile device, you should already have this covered. You can check how Google rates your mobile site with their Mobile Friendliness testing tool.

2. Check your log files

In most instances, GoogleBot’s crawling is 75-80% desktop crawler and 20-25% mobile crawler. When a website moves over to the mobile first index, you would see that flip to about 75-80% GoogleBot mobile.

3. If you have a separate mobile website…

…make sure you claim the mobile version in Google Search Console to continue to get accurate data.

4. Ensure as much primary content is delivered to all users…

…regardless of device type

5. Verify that your mobile version is accessible to GoogleBot

You can do this with the robots.txt testing tool.

6. Look into mobile-first tech like AMP

With Google making its new mobile index its primary focus, expect to see an even greater emphasis on Google’s Accelerated Mobile Pages (AMP) project to become even more important in the near future.

7. Make sure to serve structured mark-up for both the desktop and mobile version

If in doubt, you are able to verify your structured mark-up across desktop and mobile testing both versions with the Structured Data Testing Tool.

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