What are Core Web Vitals and how do they work, should I worry about them?

Question

I saw recently that Google will consider the reports of Web Vitals (Lighthouse and Search Console) as a factor of rankings, because these factors can directly interfere with the user’s experience with the page. But this is something exclusive to Google or would be a general good practice, for example, even for a Saas I must take this into consideration?

In summary, what exactly are these metrics of Core Web Vitals? It got a little confusing for me. It seems to me an imposition of Google, but you have to worry about it in web systems that has nothing to do with Google?

Answer 1

I saw that the question was asked a long time ago and I hope that the answer will still be useful. Coincidentally I had to research better on and I ended up realizing that metrics in addition to influencing rankings obviously affect the performance of your application, which will fatally affect the experience of the people who use and consequently the user satisfaction index.

I mean, there’s the technical part, but there’s a lot of user experience involved here. My current field of research is accessibility and in this case, I am focused on the simple and efficient accessibility of the information presented. If I have a problem to display this message (which may be related to the delay it is displayed to the user) I affect the experience and consequently the accessibility of the information as well.

The official page detailing each of the metrics and demonstrating which tools you use to get the reports you need is this: https://web.dev/vitals/

Summarizing the metrics:

LCP (Largest Contentful Paint): measures the time of loading the information, if it takes more than 2,5 seconds is bad...

FID (First Input Delay): measures the interaction time from the moment the user clicks on a button until the execution of the function that the button does, for example.

CLS (Cumulative Shift Layout): measures the consistency of the layout... sometimes the screen elements change places, due to an earlier action. For example, you clicked on something and something appeared on the screen that did not exist before and this caused the previous elements to scroll, which can cause confusion in the user.

Especially the latter (CLS) you have rules including in WCAG related to good accessibility practices and you can search the criteria 3.2.3 - Consistent Navigation, but all impact on the experience as a whole.

Summarizing the tools:

Chrome User Experience Report which can mainly help you with statistics on load time of information on the screen.

Page Speed Insights which is the tool that will show you how you really are and what you need to do to improve each point of the Vitals metrics. (if you install the LIGHTHOUSE plugin in Chrome, you get the same results)

Google Search Console that will unify the information into beautiful and easy-to-set dashboards.

Anyway, I hope the answer was still useful.

abs Marcelo Sales