Understanding Google Core Web Vitals
For quite some time Google has been pushing user experience as an important metric in ranking websites on its search engine. But with a multitude of metrics and tools, understanding the truth behind the quality of user experience that is delivered becomes challenging.
Web Vitals is a new initiative by the search giant to help sites understand the core metrics that are essential to delivering a great user experience on the web.
The core Web Vitals is being introduced in conjunction with the existing user experience signals. This new ranking signal is still in its early stages of development and is expected to be released later next year.
Core Web Vitals
Core web vitals are based on three aspects of user experience i.e loading speed, responsiveness, and visual stability. These are measured using three metrics, such as
- Largest Contentful Paint
- First Input Delay
- Cumulative Layout Shift
Cumulative Layout Shift
Cumulative Layout Shift (CLS) is an important metric that measures layout stability i.e it helps quantify how often users experience shifts in the content on a page.
A low CLS is often caused by images without dimensions, ads, embeds, or iFrames without dimensions dynamically injected content and web fonts that might cause an instant of unstyled content.
Largest Contentful Paint
Largest Contentful Paint measures the loading performance of the page specifically the point in the page load timeline when the main content of the page has loaded.
It can be measured using Field tools like Chrome User Experience Report PageSpeed Insights, Search Console (Core Web Vitals report), and Lab tools like Chrome DevTools, Lighthouse, WebPageTest.
First Input Delay
First Input Delay which measures interactivity quantify how users feel when trying to interact with unresponsive pages. First impressions are gold when it comes to experiences on the web.
FID essentially measures the kind of impression that your website is likely making on your users in terms of interactivity and responsiveness.
Measuring Core Web Vitals
Chrome User Experience Report Dashboard commonly called the CrUX is a great solution to measure the Core Web Vitals metrics, including Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS), as well as other diagnostic metrics like Time to First Byte (TTFB) and First Contentful Paint (FCP).
The Core Web Vitals metrics categorize performance as either “good”, “needs improvement”, or “poor”.
Additionally, to measure the overall performance of a page or site, Google uses the 75th percentile value of all page views to that page or site. This means that if at least 75 percent of the page views to a site comes under the “good” threshold, the site is classified as good under that particular metric.
On the contrary, if at least 25 percent of the page views come under the ‘poor’ threshold, the site comes under the poor performance category.
Web Vitals and Core Web Vitals is one of the best available measures to accurately measure the quality of user experience. With Google moving towards page experience as a possible metric, changes to these will have a larger impact.