In May 2021, Google launched Core Web Vitals. It is a collective term for three technical parameters that, in combination with other parameters, ensure a good page experience for users when they visit your website. The launch is an extension of the already existing Web Vitalswhich emphasises parameters such as mobile-friendliness and HTTPS.
With the launch of Core Web Vitals, Google has thus added more technical parameters to the evaluation criteria it uses to determine your website's quality and thus visibility in search results. Google has officially confirmed that the new Core Web Vitals parameters have a direct impact on your website's visibility in search results.
The 3 elements of Core Web Vitals
Core Web Vitals basically consists of three technical measurements of your website that must meet certain criteria to ensure a good site experience for users:
- Largest Contentful Paint (LCP). LCP refers to the speed of how long it takes to display the element on the page that takes up the most space. This is typically the largest image on the page. To ensure a good page experience, the LCP should be no more than 2.5 seconds.
- First Input Delay (FID). FID refers to the time it takes for the page to respond to user input (for example, when a visitor clicks on a link or button). To ensure a good page experience, the FID should be 100 milliseconds or less.
- Comulative Layout Shift (CLS). CLS refers to how much elements on the page move while the page is loading. To ensure a good page experience, the CLS should not exceed 0.1. Especially on mobile devices, the CLS score is highly valued, as page movements are clearly visible there.
A number of additional measurements of a less significant nature are also included, including First Contentful Paint (FCP), Interaction to Next Paint (INP) and Time to First Byte (TTFB). If you are curious, you can read more about these measurements in Google's own guide.
Optimization of Core Web Vitals
Use Google's free tool PageSpeed Insights to analyse Core Web Vitals on your website. The tool analyses one page on the website and gives the page a score from 0-100 on mobile and desktop devices respectively. You will also receive a detailed report with concrete recommendations on how to improve the Core Web Vitals on your site.
You should analyse different page types on the website (for example, the front page, a category page and a product page) to make sure that all pages score well. Often, improvements on one page will have a positive impact on the whole website because the pages are built on the same technical platform.
The score is calculated based on actual user data, i.e. the actual experience of visitors on your website. Please note that it is virtually impossible to achieve a score of 100. Google itself says that a page is good if it has a score of 90 or above. A page needs improvement if it has a score of 50-89, and a page is downright bad if it has a score of 0-49.
A good complement to PageSpeed Insights is the "Key Network Statistics" report in Google Search Console. It provides you with a continuous analysis of which pages on your website have a good, average and poor Core Web Vitals score, and the reason for any poor score.
