If your website fails this simple testlabeling it "not mobile-friendly," you stand to lose a significant portion of your organic online traffic a month from now. 

It's all because of upcoming search ranking algorithm changes from Google, as they further expand the mobile ranking demotion algorithm first launched back in 2013.  

"Starting April 21, we will be expanding our use of mobile-friendliness as a ranking signal," begins the statement from Google. "This change will affect mobile searches in all languages worldwide and will have a significant impact in our search results. Consequently, users will find it easier to get relevant, high quality search results that are optimized for their devices."

A recent TechCrunch study finds 75% of smartphone users access the Internet from their devices, and that's why Google says mobile must now be a priority for all businesses.

Regardless of the search ranking changes, Google says with so many users flocking to mobile, companies that don't provide a good mobile experience with their websites will be losing out to competitors that do. 

Over the last couple years, Google has strongly encouraged webmasters to focus on mobile-friendliness by increasing the visibility of sites (and apps) that are doing it well. 

The company has also made a great effort to assist webmasters in optimizing their mobile experience, by providing information such as this guide to mobile best practices. 

Gary Illyes, a Webmaster Trends Analyst at Google, recently confirmed two important aspects about the April ranking factor changes on a panel discussion at Search Marketing Expo West:

  • The algorithm will be real-time. This means that after the algorithm change goes live, you will benefit from having a mobile-friendly site as soon as Google detects the change. So while the argument is the sooner the better, there is no need to stress out if getting your site ready by the April deadline is completely unrealistic.

  • The ranking factor will be evaluated on a page-by-page basis. This means you can prioritize optimization of parts of your site, perhaps keeping some of the more difficult sections of the site for after the deadline.

Identify and Improve Your Mobile Web Optimization Status

Search Engine Land says in this piece the first thing you - or your webmaster - should do is assess your mobile web search presence.

Start by validating your site with Google’s mobile friendly test tool we also linked to at the beginning of this post.

If your site is labeled "not mobile-friendly," the tool will list the reasons why, such as the text is too small. 

Mobile Friendly Google Test

For similar insights, you can also view the Google Webmaster Tools mobile usability report, which will alert you to various mobile usability issues such as the use of Flash, and elements that are too close together.

And it goes on and on from there. The purpose of this post isn't to do a deep dive into the technical issues, but rather simply to alert people of some big changes ahead that will likely catch many unaware. 

Have you navigated your own website from a cell phone? Have you counted the actions on each page? Do you have to resize to get a really good view of certain elements? Scroll left or right? Ignore floating elements that are jumbled up? Is the text readable without zooming? 

Experts say these are the kinds of questions that need to be answered when it comes to making a site mobile-friendly. 

And because many of us need help with those kinds of questions, and making these types of changes, 2015 will likely be a good year for developers, and also for newer, mobile-first platforms that have been designed from the ground up with mobile in mind. 

"I would say to any webmaster that having a non-responsive, non mobile-friendly website is simply just no longer an option in today's world," said one commenter to a Search Engine Land post. "There is simply no way around this update. Go mobile or go home."