Web Vitals is a compilation of metrics intended to demystify the practice and art of web performance optimization. Everyone knows that a faster website typically converts more clients, and this enormous piece of advice has become the cornerstone of almost any effective marketing campaign.

However, web performance optimization is much broader than just a top-level “speed” metric.

With Web Vitals, Google recently revealed a set of three “Central Web Vitals” that will soon become factors in its ranking algorithm. While we still don’t know to what degree these scores can be used in the algorithm, this is the news several technical SEOs have been waiting for.

For several years, SEO and digital marketers have used performance optimization tools such as Pagespeed Insights to make recommendations on server speed, caching, render-blocking, asset compression, and CDN delivery. These factors remain relevant in providing a quick user experience and ultimately achieving good Site Vitals scores.

For product owners, marketing managers, and developers, Site Vitals and Core Web Vitals are essential aspects of evaluating three critical experience variables’ success using three basic metrics.

What’s the Core Web Vitals

The three core web vitals are as follows:

1. Largest Contentful Paint

(LCP) calculates the page load experience and, in particular, the perceived load speed as the score is measured on the basis of the largest painted asset in the viewport, rather than just any viewport painting (see First Contentful Paint) where the load is considered to be good within 2.5 seconds and more than 4 seconds is bad.

2. First Input Delay

(FID) tests the interactivity and responsiveness of the page after it has been loaded. Causes for large FIDs are usually sites that run a lot of main thread JavaScript processes once the browser has the code needed to paint a page, thereby delaying event handlers that allow menus, browsing, and other interactive features. 

You may be familiar with “hanging” websites when loading ads—this is exactly the metric FID scale. A strong interactivity score is when contact is treated and replied to within 100 milliseconds and is considered bad when it takes 300 milliseconds or more.

3. Cumulative Layout Shift

(CLS) tests visual consistency, and the intended user enjoys access to the web page. Visual stability is a frustration for users as it can cause confusion – or worse, incorrect usage of the platform, type, or application. 

Low visual stability can come from a variety of causes, such as assets with unknown dimensions before rendered, such as an image, video, or custom web font, or more annoying user interface blockers such as expanding advertisements and pop-up features. 

CLS is a score between 0 and 1 based on the moving distance and visual impact of the viewport feature. A score of 0.1 or less is fine, and anything above 0.25 is considered bad.

With these considerations in mind, the Impression team considered a review to understand how global sites are doing. This has been made possible thanks to the Chrome User Experience (CrUX) data collection made available to us by Google.

We found the media sector to be likely candidates for lower than average Core Web Vitals scores due to advertisements, memberships, and subscriptions that the media needed to drive in recent years to retain high-quality journalism. 

These add code bloat, rendering time, and, in some cases, layout changes, which are key ingredients to poor user experience. We don’t yet know how Core Web Vitals will be applied to a site’s ability to rank, but our hope is that those with low perceived experience will eventually be overtaken by pages providing similar news and knowledge at a higher perceived level of experience.

The Core Web Vitals Research

Our analysis of 50 global media publications takes into account aggregate daily data from each domain of the website, aggregated at the domain level where multi-page test data is available.

Because we don’t yet know how Google can weigh each of the three Vitals ratings, we’ve also summed the occurrence of ‘healthy’ and ‘bad’ scores to build our own Core Web Vitality average score by which we’ve listed the sites in the graphic below.

Of all the websites reviewed, only one site – seoholic.net – has averaged ‘healthy’ experience in the three categories across the time span.

Most sites have achieved a reasonable First Input Delay, but many have been lowered either by LCP (perceived load speed) or CLS (visual stability) ratings, with the worst-performing top 50 place – francious.fr – providing a ‘good’ CLS experience of less than one-fifth of the time. 

Across most of the sites we reviewed, the biggest layout change was due to unoptimized media, delayed JavaScript rendering, and incredibly broad cookie policies.

Take, for example, the UK news website mirror.co.uk as it makes for a person. You can see it goes through several states until it actually becomes interactive.

It is also evident from the data that organizations have a significant web performance agenda that is not yet fully established. We attribute those sites with a tight web-based cluster of Vitals scores to those with an emphasis on web results and those with more varied experiences than those organizations that have yet to prioritize user experience.

Looking at the worst results of the top 50, you can see this difference in action.

Outside the media business, what does Core Web Vitals mean for webmasters?

There is currently no fixed date for updating the Google algorithm. However, like past updates, Google updates usually drive webmasters in one direction—to provide better, quicker websites for users. 

This means that you don’t need to wait for the update to introduce the technical improvements that will boost your Web Vitals ranking. This means that you can be a few steps ahead of your online search competition once these ranking factors come into play.

Google has provided you with a range of research tools to test the websites and gain details on progress and debug to enhance these metrics. 

With sample code, you can customize real user tracking and track ever-changing lab data in PageSpeed Insights and your own browser experience in the Chrome DevTools Performance panel.

The 2021 Impact of Core Web Vitals: What We Know

If you skipped Google’s first and/or second announcement about Core Web Vitals: Google Search Console is now able to quantitatively show webmasters their areas of user experience enhancement – including loading, interactivity, and visual stability.

Starting in May 2021, these Core Web Vitals will become a clear Google ranking warning.

Although Google has acknowledged the value of user experience for years, these two announcements have raised the stakes by putting SERP’s visibility on the line.

Not to mention, Google would make websites with “weak” Core Web Vitals ineligible for a viable “Top Stories” carousel – and drop its previous AMP eligibility criteria.

Google has not announced (and is doubtful, in my opinion) the actual ranking fluctuations that SEO pros can anticipate from this imminent signal.

Questions to ask yourself if you don’t know how to prioritize Core Site Vitals

To help you determine if a Core Web Vitals campaign will support your team from prioritizing early in 2021, I would like to ask you the following questions:

  • What is the starting point of your website?
  • Do you have tens of thousands of “bad” URLs, including your most important pages?
  • Or just a handful of URLs that “need improvement?”
  • What else is on your roadmap? 
  • What production tools are available to you?

Suppose you have a range of important SEO goals on the horizon or restricted bandwidth growth. In that case, you will need to make some collective, cross-departmental decisions about what will have the greatest business effect.

Are you a news publication?

News publications that generate a large amount of search traffic from the “Top Stories” carousel (or wish they did) should certainly consider optimizing Core Vitals.

In May 2021, Google will carry out new ranking signals called the “Core Web Vitals” to recap what we’ve learned in this article.

Although Google has been stressing the value of improving the user experience for years, the stakes will be raised in May when this becomes a quantifiable ranking signal as part of the overall page experience score.

The surveyed and interviewed SEO professionals fell through a broad spectrum when asked about their predictions about how this new ranking signal would affect the SERPs.

(Sites that neglect Google’s year-long warning can be slammed).

There are various factors to consider when determining how to prioritize the Core Web Vitals campaign for your clients’ websites.

  • The starting point of the website.
  • Development services that are open to you or shared with other agencies.
  • The website industry.

However, referencing reputable data points where possible and breaking up large tasks into smaller tickets can allow SEO professionals to make steady progress on the initiatives they are most concerned about.