What is “Largest Contentful Paint” (LCP)?
LCP is a metric that captures loading performance. Your largest content should begin to appear, or be “painted,” quickly. Google standards of practice dictate that a website’s LCP should occur within the first 2.5 seconds of a page’s loading to be considered part of a good user experience.
What is “Cumulative Layout Shift” (CLS)?
CLS is a metric that defines visual stability. Quite literally, this means that content should be stable and readable within a page. If a page’s continual loading causes text and images to jump around or change the dynamics of your page, then users can find themselves losing their place or frustratingly clicking in the wrong places at the last second. CLS measures the largest layout shift that occurs during the lifespan of a page’s activity. Sites with a layout shift score over 0.1 are considered unstable and need improvement.
What is “First Input Display” (FID)?
FID is a metric used to track a page’s interactivity. Interactive websites are good websites. But websites that prompt interactivity need to be markedly efficient in handling button clicks and requests. From the time users initially dynamically interact with your page (click a button, for instance) to the time that your site begins to process the request, FID is the name of the game. To provide a good user experience, your website should have an FID score on all pages of 100 milliseconds or less.
How are Core Web Vitals measured across the variety of internet speeds and devices?
Because there are so many variables to account for within each user’s unique experience, Core Web Vitals are rewarded when they serve the majority of your audience the majority of the time. Google rewards core vitals that track in the 75th percentile and above for all three metrics, segmented across the traffic from both desktop and mobile devices.