Core web vitals

Core Web Vitals are a set of essential metrics that measure the user experience on a website, including loading speed, interactivity, and visual stability.

Core Web Vitals are a set of specific metrics that measure the performance and user experience of a website. These metrics focus on three key aspects: loading, interactivity, and visual stability. They are designed to provide website owners and developers with actionable insights into how well their site is performing and how it can be improved.

The first metric, Largest Contentful Paint (LCP), measures the time it takes for the largest element on a webpage to load and become visible to the user. It helps assess the loading speed of a website, with a target of under 2.5 seconds being considered good.

The second metric, First Input Delay (FID), measures the delay between when a user interacts with a webpage (such as clicking a button) and when the browser is able to respond to that interaction. A lower FID indicates better interactivity and a more responsive website. A target of under 100 milliseconds is recommended.

The third metric, Cumulative Layout Shift (CLS), measures the amount of unexpected layout shifts that occur during the loading process. These shifts can be frustrating for users as they can cause buttons or links to move, leading to accidental clicks. A lower CLS indicates better visual stability, with a target of less than 0.1 being considered good.

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