Core Web Vitals
As the digital landscape continues to evolve, the importance of website performance, speed, and user experience has become increasingly clear. In response to this need, Google has introduced a new set of metrics known as Core Web Vitals, which aim to measure the key aspects of a website's user experience.
Core Web Vitals are made up of three key metrics: Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS). These metrics are designed to measure the performance, speed, and stability of a website, respectively, and can provide valuable insights into how well a website is meeting the needs of its users.
Largest Contentful Paint (LCP) measures the time it takes for the main content of a page to load, and is an important factor in the perceived speed and performance of a website. A good LCP score is typically under 2.5 seconds, and a score above 4 seconds is considered poor.
First Input Delay (FID) measures the time it takes for a page to respond to user input, and is an important factor in the perceived interactivity and responsiveness of a website. A good FID score is typically under 100 milliseconds, and a score above 300 milliseconds is considered poor.
Cumulative Layout Shift (CLS) measures the stability of a page as it loads, and is an important factor in the perceived user experience of a website. A good CLS score is typically under 0.1, and a score above 0.25 is considered poor.
In addition to these three key metrics, Google also provides a number of other performance metrics and tools that can help developers understand and optimize the user experience of their websites. These tools include the PageSpeed Insights tool, the Lighthouse tool, and the Chrome DevTools performance panel.