The difference between fp and fcp of the website
FP (First Paint) and FCP (First Contentful Paint) are two indicators related to webpage performance, which are used to measure the speed of webpage loading and user experience. The differences between them are as follows:
- First Paint (FP): FP refers to the point in time when the browser first paints pixels to the screen. In other words, it's the beginning of browser rendering, the moment when the user sees something rendered on the page. FP doesn't require the content to be actually readable or meaningful, as long as there are pixels to start drawing.
- First Contentful Paint (FCP): FCP is the point at which the browser first paints meaningful content on the page. Specifically, it represents the real, meaningful page content, such as text, images, or other visual elements, as first rendered by the browser on the screen. FCP marks the first part of the page that users can see.
To sum up, FP is concerned with when any pixel starts to be drawn, while FCP is concerned with the time when the first meaningful content is drawn. FP usually happens earlier than FCP, because it only needs to draw pixels, and does not need to wait for the real content to load and render.