What are Core Web Vitals?

In May 2020, Google announced on its Webmaster Central Blog that it would be updating its organic search algorithm to incorporate page experience as a ranking signal in the near future. As the web evolves to be faster and more user-centric, this announcement was not particularly surprising; but it is notable for two main reasons:

  1. Google rarely provides explicit information on ranking factors

  2. Google never provides advance notice of algorithm changes

So what’s the deal? Why is Google—which is usually so tight-lipped about ranking factors—suddenly so transparent about how to rank?

I have two theories: On one hand, this algorithm change will significantly impact lots of rankings (think: the 2011 Panda update that impacted 12% of all pages in Google’s index) and there is real concern about the fallout. On the other hand, Google is providing ample notice and comprehensive documentation to underscore its dedication to “small businesses” by making the company seem more welcoming and friendly (to court more advertising dollars in the long run). Either way, page experience is not something that site managers can ignore any longer.

But what exactly are page experience metrics? And what can SEOs and site managers do to prepare for these new ranking factors?

Here’s what you need to know about Core Web Vitals.

 
 

Core Web Vitals Defined

Core Web Vitals is an initiative by Google that is designed to help site managers quantify the page experience of visitors and identify areas of improvement. These page metrics provide unified and simplified guidance for quality signals that are essential to delivering a great user experience on the web.

“Site owners should not have to be performance gurus in order to understand the quality of experience they are delivering to their users.”
— Google

Core Web Vitals apply to all web pages and should be measured by site managers starting immediately, as these metrics will soon contribute to the performance scores in the Chrome User Experience Report, PageSpeed Insights, and Search Console.

Google has stated that the exact metrics will likely change over time, but the current 2020 Core Web Vitals focus on three aspects of the user experience:

  1. Loading

  2. Interactivity

  3. Visual Stability

 
Image by Google Developers on web.dev

Image by Google Developers on web.dev

 

  • Largest Contentful Paint (LCP): measures loading performance. To provide a good user experience, LCP should occur within 2.5 seconds of when the page first starts loading.

  • First Input Delay (FID): measures interactivity. To provide a good user experience, pages should have a FID of less than 100 milliseconds.

  • Cumulative Layout Shift (CLS): measures visual stability. To provide a good user experience, pages should maintain a CLS of less than 0.1.

For each of these key metrics, site managers should strive to fall within the 75th percentile of page loads, segmented across mobile and desktop devices.

Getting Started with Core Web Vitals

Data collection is the first step; a solid understanding of how a site is functioning will help prioritize projects that will drive the desired performance. Fortunately, measuring Core Web Vitals requires minimal code changes and can be accomplished using freely available tools.

There are two main approaches to data in regards to Web Vitals: field data and lab data.

Field Data

Field Data—also known as Real User Monitoring (RUM)—captures the performance experienced by a site's actual users; this is the data that Google uses to determine whether or not a site meets the established Core Web Vitals thresholds.

Field Data collection tools include:

Lab Data

Alternatively, Lab Data—also known as synthetic data—is collected from a controlled environment, rather than actual users. Instead of relying on actual user experience analysis, lab data is typically collected from pre-production environments and tested against benchmarks.

Lab Data collection tools include:

Core Web Vitals Timeline

Google stated that it will provide at least 6 months notice before this algorithm update is rolled out. But my suggestion would be to start focusing on these numbers now to be the most prepared.

A final note: Google has alluded to the idea that page experience signals will essentially act as a “tie-breaker” when ranking a page. So for example, if two pages both provide similar great content, the page with the stronger Core Web Vitals metrics will rank higher in SERPs.

Tl;dr: I believe that great content will continue to outrank a great page experience.

Adam Harkness