What is mobile-first indexing?
Mobile-first indexing is simply how Google crawls and indexes the web. Instead of looking at the desktop version of the page, Google looks at the mobile version of the page. In more simple terms, Google is crawling and indexing your web page based on how it renders on a mobile phone versus a desktop computer.
Why does it matter?
If your desktop pages are different from your mobile pages both in terms of content and structured data, then your rankings may be impacted. Google has generally moved sites that have parity between mobile and desktop pages first to mobile-first indexing. But with over half of the search results now indexed through mobile-first indexing, it is just a matter of time until your web pages are moved over as well.
You do not have to have a mobile site to be in the mobile-first indexing, as Google will index desktop sites as well. But, it’s going to be hard to rank if your site is not mobile friendly. So there’s work to do for all of you who have not have a mobile-friendly site yet.
What do you need to do? Check out Google’s mobile friendliness test and check whether or not your site is mobile friendly. In our experience, this is a minimum requirement. If your site does not pass this test, your mobile version is bad.