Everything about Google’s Core Web Vitals 2021

Google Core Web Vitals 2021

Just when you had a ray of hope with seo, google spilled new beans for you to collect.

Unless you are living under rock, you may be aware that seo is going to change all together! It is no more just about the content in the page but now this is about user experience of the web page.

So if you are a small business, or an internet entrepreneur and you are wondering what is that? In this post we are going to clear all your doubts.

But before that, it is supposed to be released in mid of may 2021, but google decide to postpone it.

Google Core Web Vital update is postponed to mid of June 2021 – Google Blog

Some people are also calling it as Page Experience algorithm also, but you may call it ever you like! Down the line it is going to remain same.

In this post, we are going to cover following points

  • What is Google Core Web Vital Update?
  • Why do we need it?
  • Seven Signals for Page Experience.
  • How to check if you are ready for it?
  • Frequently asked questions
  • Conclusion

What is Google Core Web Vital Update?

Google core web vital update is an addition to the algorithm where google is focusing on web pages which provide better user experience to the end user.

Before this, every web page was designed just for consuming content! But as things have evolved, google realised that how content is consumed is also very important. The end user experience should also be rich.

Google wants to make sure content should not just be consumed but also be experienced.

Why do we need it?

10 years ago, internet was not as fast as we have today. Those days, users was aware that page is going to load slow. Slow internet meant less features which meant focus was on content than anything else.

There were no flying popups which randomly popped in middle of web page, but it all changed when internet speed started getting faster.

Marketers thought, with more power comes more responsibility for me to show one more popup before reaching the boiling point of the visitor.

This annoyed the visitors, they started the dislike the experience they were getting on the page.

It does not mean by just improving page experience, you will rank 1st on google. They have mentioned 7 signals which they will be looking in your web page.

Seven signals for Page Experience

As mentioned above, just have a good page experience is not enough, google is also look at 7 different signals to decide if the page experience is good or not.

Google has given guidelines which it is going to look to rate the page experience.

What are those 7 signals?

  • Mobile friendliness
  • Safe browsing
  • HTTPS/SSL, or encryption
  • Intrusive interstitials
  • Largest Contentful Paint (LCP)
  • First Input Delay (FID)
  • Cumulative Layout Shift (CLS)

Mobile Friendliness or Responsive Web Page

Lets try to understand, why mobile friendliness is important. You can look at 2 images below, the image on left has clean ui which is helping you consume the content from mobile phone, while on the right hand side, you have desktop ui which makes it impossible for users to consume the content.

Bad experience, results in bad reputation and that make user stay away from the website altogether.

Mobile Friendliness was introduced in 2015 but there are still some websites which are not following the convention.

Having your website as responsive will enable your layout to adapt to screen of any size. So you don’t have to worry about creating separate version of web pages for separate size of screens.

Safe Browsing

When a user is visit your website, he should not be prompted to download malicious files. Your website should not serve any content which comprise user’s security such has cookie theft, session hijacking, or disabling user’s ability to take action.

This should very simple but this is one of the most important factor, if your website is vulnerable, make sure you scan your website with services like https://sitecheck.sucuri.net

Note Google does not like website which are vulnerable.

HTTPS / SSL aka Lock Sign

If your website does not have a valid ssl certificate and is not serving the content over http, then even browsers are going to discourage users to even enter passwords, or provide credit card information.

Websites without a valid ssl certificate are vulnerable to man in the middle attack.

If you are wondering how you can have an ssl certificate in your website, you can take advantage of free services like Lets Encrypt

The safest and fastest place for you would be to reach the domain service provider, and they can help you setup ssl certificate.

Intrusive interstitial

I want you to block the content with one more banner – said no one ever

The more you annoy your user with interstitial, the more users are going to stay away from your website.

These days websites have fixed banners ads in bottom of view port, cookie poup, email popup, exist popup and the ultimate allow notification

Nobody likes that, and google also understood that.

However, google has whitelisted few of interstitial like accepting cookies or age limit popups.

Largest Contentful Paint (LCP)

Nobody likes slow website – an average internet users

Yes, just like you! Nobody likes show websites, everyone likes when information is presented to them as soon as they click on that link.

Largest Contentful Paint property suggest that biggest text block or biggest image of your web page should load within 2.5 seconds otherwise it will give bad user experience or they go back.

Source: https://web.dev/lcp/

First Input Delay (FID)

Imagine this, you are sitting is one of the best restaurant of your neighbourhood! You have ordered the food but it is taking forever to come.

Nobody likes that, your angry is just growing.

First Input Delay helps you understand how fast a user can start interacting with the elements on the page.


  • Add to cart
  • Change size of product
  • Change the currency to local currency
  • Change the language

If a user is blocked from taking actions, they assume that the web page is broken it is best to stay away from it and they click back.

Google suggest that an ideal web page should have FID less 100 milliseconds.

Cumulative Layout Shift (CLS)

Let’s try to understand this with an example video below!

You can see, an app download banner loaded out of no where, which result in user clicking on the wrong button.

CLS helps us understand, the bad user experience due to constant shifting of the layout.

This is quite common these days with when an element popups randomly without the knowledge of the end user.

It is recommended, the desired action should only happen when use expects it to happen.

Google is suggesting your CLS score should be 0.1 or less

Source: https://web.dev/cls/#what-is-cls

How to check if you are ready for it?

You must be nervous, how are you going to keep all things in mind. How are you going to find out if you are even ready for it.

Don’t worry, there are many tools which are available to get you ready for it.

Google provides various tools to measure and keep you updated.

You can use Google PageSpeed Insights tool, which is a free tool which not only finds the problem but also provides you the solutions.

For Advance users or developers only!

If you are a developer, Google Chrome comes with Lighthouse, an inbuilt tools for developers to test their applications when it is under development.

And if you wish to test your Core Web Vital score when users are using your website, they you can use Web-vitals Javascript Library. This will be integrated with your web applications and you can send data to your analytics tool to analyse.

FAQ – Core Web Vitals

Will it impact on my current seo score?

Yes, the core web vital or page experience algorithm will impact your seo score if you have not implemented it.

How important it is compared to traditional seo optimisation?

Traditionally you optimised your content, you added keyword and what not! Now you also have to make sure that your page experience is optimised so end user the can consume the content.

What is a Good Cumulative Shift Layout Score?

Google suggests that a good CLS score should be 0.1 or less.

What is good Largest Contentful Paint score?

An ideal LCP score should be 2.5 seconds or less.

What are seven signals for page experience algorithm?

The main seven signals are

  • Mobile friendliness
  • Safe browsing
  • HTTPS/SSL, or encryption
  • Intrusive interstitials
  • Largest Contentful Paint (LCP)
  • First Input Delay (FID)
  • Cumulative Layout Shift (CLS)

What is a good First Input Delay score?

An ideals score for FID should be 100 milliseconds or less.


So, it is no more just optimising around the content, it is now also about the end user experience.

You can no longer that bully restaurant, who is not known for it’s food but knows for it’s bad service.

This update is going to majorly affect the eCommerce website owners, because these website are always on edge.