Website owners have about six weeks to make sure their sites are optimized for viewing on mobile devices if they want to maintain their ranking in Google's search results.
Starting in May, Google will give even higher ranking in search results than it currently does to Web pages where text is easily readable on mobile devices that are more easily clickable—without any tapping or zooming—and where the page avoids unplayable content or scrolling.
Sites that already meet the company's metrics for mobile-friendliness will not be affected by the change to Google's mobile search algorithm, software engineer Klemen Kloboves announced this week.
However, sites whose pages do not measure up can expect to see a significant decline in mobile traffic from Google Search, the company has previously noted.
"Getting good, relevant answers when you search shouldn't depend on what device you're using," Kloboves said. "You should get the best answer possible, whether you're on a phone, desktop or tablet."
Google had announced its plans to give mobile-friendly sites higher search ranking last April. At the time, the company had said the change to its search algorithm would affect searches on mobile devices in all languages globally.
The change would only apply to individual Web pages and not the entire site. In other words, a site that has optimized some of its pages for mobile viewing can expect those pages to get preferential treatment in Google's mobile search over pages from the same site that are not optimized.
Google has said, and Kloboves this week reiterated, that content quality would continue to be one of the major factors that its algorithm considers when assigning a rank to a Web page. "So even if a page with high-quality content is not mobile-friendly, it could still rank well if it has great, relevant content." Kloboves said.
And Web pages that rank poorly because they have not been optimized for mobile devices can always attain their previous status once they have been optimized.
As it did when Google first announced the change to its search algorithm, the company this week published a link to a Mobile-Friendly Test site that Web operators can use to test their sites. The company has also set up a guide that webmasters can use to tweak their sites for mobile viewing.
While pushing for the change, Google has acknowledged that making a site mobile-friendly may not always be easy or inexpensive.
One way that a site can go mobile for free is to use a responsive template or theme from a company like Drupal, Joomla or WordPress, Google has said. Such templates automatically adjust the content to the display, the company has noted. Going mobile can also be relatively easy for organizations that have the internal skills.
However, it can cost time and money for organizations that need to hire a developer. Operators of Websites that were built several years ago might find it easier just to start from scratch and take advantage of new development tools to make their sites more mobile-friendly, Google said.
The tech giant has a lot at stake in ensuring a better online experience for mobile device users. With more people accessing content with smartphones, tablets and other mobile devices, a lot of the company's future ad revenue will come from the mobile world.