The first is Largest Contentful Paint LCP. In layman's terms, how fast does the page load? It's a very simple concept. The largest image, video, and text in a window on your computer screen is largely affected by how long it takes to render.
That's what Google is looking at. How fast does the largest thing on a computer screen, whether it's a desktop page or a mobile page, the largest image, video, text, etc., load? The answer to this question is simple, it is affected by server time, CSS, JavaScript, client-side rendering.
Cumulative Layout Shift CLS
The second thing is cumulative layout shift CLS, which is what ukraine mobile database Google is looking at in terms of how quickly a page can become stable. We’ve all had that experience of loading a page on our phone, going to press a button, and then at the last second the button moves, and we end up clicking something else and the page has an unexpected layout change.
That's a bad user experience. That's what Google is measuring with cumulative layout shift. How fast is it stable? The number one reason for web pages to be unstable is that image sizes are often not defined. So if you have an image that's 400 pixels wide and 400 pixels high, you need to define those pixels in the HTML. There are other reasons too, like animations and things like that. That's what they're measuring with cumulative layout shift.
First Input Delay FID
The third thing in these Core Web Vitals metrics is First Input Delay FID. This question basically asks how fast is the page interactive? In other words, when a user clicks something, a button, or a JavaScript event, how quickly can the browser start processing and producing results?