Google is switching to a mobile-first index in 2018, wherein rankings for desktop and mobile devices will be based on a site's mobile experience. Google's
Google is switching to a mobile-first index in 2018, wherein rankings for desktop and mobile devices will be based on a site’s mobile experience. Google’s “Mobile-Friendly Test” will identify if a site is mobile optimized and can, also, suggest performance improvements.

Most searches on Google are from mobile devices. In 2018, Google will judge your desktop and mobile sites’ worthiness to rank based on your mobile implementation.

If your mobile experience isn’t already as fast or complete as your desktop experience, now is the time to prepare. In that vein, Google released some advice this week on moving to a responsive site. Responsive design is the best avenue from an search engine optimization perspective, certainly, but it comes with some hefty architecture changes.

As you build your budgets for 2018, make sure they contain improvements to your site’s mobile experience.

What Is the Mobile-first Index?

Since its inception, Google and other search engines have been desktop-first. They indexed and ranked content — regardless of whether it was designed for mobile, tablet, or desktop devices — based on desktop ranking signals. This made sense because searchers were primarily using desktop computers.

Now, however, the reverse is true. More Google searchers use smartphones than any other device. Therefore, Google is swapping out its entire index to a mobile-first orientation.

There have been signals around this mobile focus for years: “Mobilegeddon” back in 2015, wherein Google included mobile-friendliness as a ranking signal, and warnings for almost a year about the coming of a mobile-first index.

Google has been testing its mobile-first index invisibly with a growing number of searchers, fine-tuning it and getting it ready for prime time. While there isn’t a firm launch date, it’s expected to debut in 2018. Google originally planned the launch for end of 2017, but…