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Core Web Vitals

Core Web Vitals

Core Web Vitals is a set of metrics introduced by Google that aim at helping you measure the quality of user experience on a website. The metrics themselves are part of a larger set of metrics, Web Vitals, and are defined as the three most important metrics to measure the quality of user experience.

The Core Web Vitals Metrics

The three core web vitals metrics are the largest contentful paint, first input delay, and cumulative layout shift, and they measure the loading, interactivity, and visual stability of the webpage.

  • Largest Contentful Paint, LCP: measures loading performance with the perceived time the page’s main content is likely loaded. It should be less than 2.5s.
  • Interaction to Next Paint, INP: measures website or application's responsiveness. An INP equal to or less than 200 milliseconds means your page has good responsiveness.
  • Cumulative Layout Shift, CLS: measures visual stability. The layout should be visually stable and keep a CLS of less than 0.1.

Measuring Core Web Vitals

You can measure the core web vitals using the web vitals open-source library, or you can use the Chrome web vitals browser extension, which requires no coding from your side.

PageSpeed Insights now also measures the core web vitals metrics directly. Or use tools such as GTmerix and SpeedVitals.

You can use the Web Vitals extension now as it shows you more debugging information to help you identify the root causes of Core Web Vitals issues.

When it comes to Core Web Vitals for SEO, the only place to check is Search Console, which uses data from the Chrome User Experience Report, or CrUX. The data collected by CrUX is available publicly through a number of tools and is used by Google Search to inform the page experience ranking factor. (Source: here).

Measuring Core Web Vitals

Measuring Global Site Performance

When optimizing for site speed, it is vital to measure the performance from different locations globally. Lighthouse metrics is an excellent tool for doing so, and it measures the site speed from six other locations giving you a good overview of the site performance from around the globe.

Measuring Global Site Performance: Performance scores worldwide.

Core Web Vitals Technology Report

Svelte, Astro, Next, or Remix for your online store? Understanding which frontend framework has the best CWV can be valuable when deciding which framework to use. 

The Core Web Vitals Technology Report is a comprehensive analysis of website performance. It provides a detailed assessment of a website's performance across three Core Web Vital metrics, helping businesses identify areas for improvement and optimize their site for a better user experience.

Core Web Vitals Technology Report

Importance of Core Web Vitals

Improving Core Web Vitals has a positive impact on your user experience, and it may have an impact on your search engine ranking. Google already started a couple of times that Page Experience signals (and Core Web Vitals as a part of them) will not be stronger ranking signals than content-related ones.

While we don’t know the actual weight they are bringing with them in the ranking algorithm, we know they matter. Have a look at our research on how site speed affects SEO and Google rankings.

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