Core Web Vitals - a new update for Google’s search ranking.


Google is the largest search engine, so no wonder they use a wide variety of algorithms to rank sites in the search results. More than 200 signals are used, and now and then, Google adds new ones.

About a month ago, the search system started rolling out a new update which will be fully available by the end of August. It is called Core Web Vitals (CWV). Its’ purpose is to improve user experience on the Internet. Quality content still matters, but it is essential to ensure that access to it is convenient for the users.

So, the factors that became really important with this update are:

Largest Contentful Paint (LCP) - it is all about content loading.  The algorithm analyzes the time to render the page, and it should be less than 2.5 seconds to get a “Good” mark.

First Input Delay (FID) - that is related to interactivity. This parameter records the time between the user’s action and the moment page handles it. It should be less than 100 milliseconds to be considered as “Good”.

Cumulative Layout Shift (CLS) - is a parameter that describes visual stability. The best mark is zero, and every unexpected layout shift on the page adds some points to this parameter. The more points - the worst the result is.

Overall URL status will be calculated based on the lowest result on a particular device type.

Google says that there are three possible ratings - Good, Needs improvement, and Poor. The exact numbers for those parameters are as follows: 

  Good Needs improvement Poor
Largest Contentful Paint <=2.5s <=4s >4s
First Input Delay <=100ms <=300ms >300ms
Cumulative Layout Shift <=0.1 <=0.25 >0.25

The detailed information about the Core Web Vitals is available here.

It is crucial to pay attention to this update since, according to the information from Google, CWVs will become an official ranking factor, so if there are two pages with relevant content, the one with better CWVs will be displayed higher in the search results.

How can you improve Core Web Vitals?

Largest Contentful Paint: 

  • remove everything you don’t need. Any third-party scripts and unnecessary images can potentially slow downloading;
  • optimize pictures if it is possible;
  • enable lazy loading, so the images will show up only when a user scrolls to them;
  • upgrade your website hosting.

First Input Delay: 

  • remove unnecessary scripts (as for LCP). This may significantly improve the rating of your site;
  • review the rest of the scripts and optimize or minimize them if that is possible;
  • pre-load some content in the background and rely on the browser cache, so the content shouldn’t be loaded when users interact with the site.

Cumulative Layout Shift: 

  • the best way to get a good rating is to set proper dimensions for all the page elements preliminary. Usually, most location shifts are caused by advertisements or media loading. So investigation using such tools as Lighthouse, DevTools performance panel, and Chrome User Experience report will help you determine possible issues.