Update – Google mobile-first index


Rob Marsden

Head of Digital - Earned and Owned

Technical SEO

This post is an update to Google’s November 2016 announcement that they had started experimenting with making their index mobile-first.

History – mobile searches overtake desktop

Historically, mobile search results have been determined by desktop content with a ranking boost given to pages that meet Google’s mobile-friendly criteria. A mobile-first index is a shift from this and mobile content will instead be the primary source used for indexing and ranking.

It was in May 2015 that the company first officially stated that mobile searches had overtaken desktop so the fact that a mobile-first index is on the horizon didn’t come as a great surprise.

Update – what we know (and don’t know) to date

We don’t yet know the full details or when this will go live, but we’re keeping a close eye on things and wanted to share with you what we know to date.

  • Responsive sites should be fine – problems could occur when you serve different and/or abbreviated content on the mobile version of a site
  • If a mobile site doesn’t exist, Google will continue to index your desktop site just fine even when using a mobile user agent – of course, non-mobile pages will not receive a mobile-friendly ranking boost (which Google has said will still apply)
  • Google is trying to make it simple for webmasters so that canonical and rel=alternate tags shouldn’t need to change when a separate mobile site is being used
  • To speed up the mobile version of a site, some webmasters have removed structured data mark-up. Because the new index will be using mobile content, this will need to be added back in if you wish to retain that data
  • Content that is behind some sort of ‘click to expand’ button was always devalued in the desktop index, but Google has said that if this is implemented on mobile for UX reasons, it will carry the full weight and should rank as well as the immediately visible content on the page
  • Google have been pushing Accelerated Mobile Pages (AMP) hard over the last year or so, but AMP content is not a replacement for missing mobile content. The new mobile-first index will determine rankings based firstly on the mobile version, however if there is no mobile version of the page it will then utilise the AMP version for the new index.
  • Meta data pixel width limits are likely to be reduced, so the way these are written and optimised will need rethinking
  • The mobile-first index will not be a second index – there will still only be one index but it will flip from desktop-first to mobile-first.

There are still a few unanswered questions which we’ll find out as Google makes more announcements and we see the new index in action. One of the main questions is around links, which are are still a big part of the way Google ranks a page – we still don’t know how this will be impacted by the different way people link on mobile:

Google’s Gary Illyes was asked about links on Twitter but said that it was too early to say so it will be interesting to see how this plays out:

How we can help

If you are concerned about how this change might impact your website, we can carry out a mobile audit to make sure that you’re ready for it and the impact to your site is minimal.

Please contact us for more information.