Core Web Vitals meaning in English

Core Web Vitals

What are Core Web Vitals?

Core Web Vitals are a set of page experience metrics created by Google which have now been built into the algorithm as a ranking factor, combined with existing signals such as page speed and mobile friendliness.

The primary metrics that make up Core Web Vitals are Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS).

Each Core Web Vital measures a different aspect of the page loading process.

Google give different weight to the various Core Web Vitals, with the ultimate goal to encourage websites to improve site experience overall for users.

Largest Contentful Paint (LCP)

Largest Contentful Paint

Largest Contentful Paint measures the time it takes for the largest visible content item (such as a text block or image) to load.

First Input Delay (FID)

First Input Delay

First Input Delay measures the amount of time/delay between a user interacting with a webpage to when the browser is able to begin processing the said action.

Cumulative Layout Shift (CLS)

Cumulative Layout Shift

Cumulative Layout Shift is a metric that measures unexpected shifts/movements in layout experienced by users of a webpage.

Web Vitals

Google also has other user-experience metrics which are not primary Core Web Vitals, including:

  • Speed Index (SI)
  • Total Blocking Time (TBT)
  • First Contentful Paint (FCP)
  • Time to Interactive (TTI)

When were Core Web Vitals added to Google as a ranking factor?

Core Web Vitals were first announced in May 2020 by the Google Chrome team, scheduled to become a ranking factor in May 2021.

This date was then revised to June 2021 in order to give webmasters more time to prepare.

Core Web Vitals are now fully integrated in the Google algorithm as a ranking factor.

How can I check the Core Web Vitals for my site?

There are various tools and sources of information for Core Web Vitals measurement.

Lab testing

To test your live site you can use Google's PageSpeed Insights tool, or Lighthouse via Chrome Dev Tools.

These tools will run a test for the URL you enter and give you a report which shows your Core Web Vital scores.

Field testing

If you get a sufficient amount of traffic you can find out how your website is performing via the Core Web Vitals report in Google Search Console.

You can also check the Chrome User Experience Report (CrUX) results for a website if there is enough data.

Why are Core Web Vitals important?

Improving the Core Web Vitals for a website can be beneficial for various reasons:

  • User experience
  • Rankings in Google
  • Traffic and sales

As well as benefiting your Google rankings, improving your Core Web Vitals should directly improve the user experience for the people visiting your website.

This in turn will likely lead to an increase in both traffic and even sales.

How do I improve the Core Web Vitals for my site?

To get top Core Web Vitals scores can require work in multiple areas, including looking at your server & CDN setup, caching, images, a lot of on-page optimisation, Core Web Vitals testing and monitoring.

Need help with your Core Web Vitals? Search Candy offer Core Web Vitals consultancy.


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