Summary of Google’s Mobile First Index

Last month at Pubcon Google announced their Mobile first index. Below is a quick summary of what you need to know, I’ve added a few resources at the end that go into the topic in much more detail. The obvious questions about the announcement are ‘What is the mobile-first index?’ ‘Why is Google making the change?’ and ‘How will it it affect your site?’ below are the answers:

What is the mobile-first index?

Previously Google’s ranking factors were based on your desktop performance, with mobile rankings being based on desktop experience. The new index will reverse this, your desktop rankings will be based on your mobile experience.

Why is Google making the change?

It’s been over 18 months since mobile searches overtook desktop searches, this trend continues to increase so it’s important for Google to take this into consideration. With most of their searches being mobile it doesn’t make sense to have a desktop first index.

How will it affect your site?

• Content in expandable tabs previously had slightly lower weighting but will now have better weighting as it benefits UX on mobile
• If you have less content on the mobile version of your site it can cause an issue - hence the importance to be responsive
• The roll out is still in the testing stage, it’s expected to be a few months until they fully roll it out
• Use fetch as Google in Google Search Console, specifically the smartphone user agent, to understand how Google views your mobile site vs users
• Ranking factors will now be mobile first, so the speed of your mobile site will affect desktop rankings. Use Site Speed Tool, get a free report from think with Google or pay for a tool like gtmetrix.com or Pingdom   
• During the roll out and testing there will be 2 indexes, eventually just becoming the one: mobile-first index
• You do not need to update your standard website canonical set-up
• It's a global roll-out, not regional
• If your site set up involves different content for mobile and desktop, you may need to make some changes to your site

More detailed resources:

1. FAQ Mobile-First - Search Engine Land
2. Background To Mobile First - Search Engine Land
3. Mobile First Changes - SEM Post
4. Unanswered Questions Through Twitter - JLH Marketing
5. Google's Official Announcement - Google Blog