How quickly can the user recognize content on the website? Google uses LCP to measure when the largest visible content block (in terms of visual presentation, not data volume) is displayed to the user. This can be text, images, or videos, for example. Since the largest element is usually loaded at the end and it’s often the main content element on the page, Google can get a very good impression of how long it takes for users to read or interact with the website.
With LCP, the search engine manufacturer has developed an alternative to older metrics such as load or DOMContentLoaded. These metrics tend to provide information that’s more on the theoretical end. Largest Contentful Paint, on the other hand, relates much more to the actual user experience. The very similar value First Contentful Paint (FCP), on the other hand, simply indicates how fast the first element was loaded. In many cases, however, this is completely irrelevant to the actual content of the website. Similarly, the First Meaningful Paint (FMP) metric has proven to be too complex and error-prone in the past.
As a guide, Google says that 2.5 seconds should cover everything from the first time the website is called up until the Largest Contentful Paint appears to users. It is important that this value also applies to all users. Values that you achieve as a webmaster in tests can differ greatly from the experience of different users.
The following tips can help you improve the LCP value:
- Use a framework instead of a large HTML page, so that you can better control how different elements on the page play out.
- Use a content delivery network so that a user’s location doesn’t have any influence on server access.
- Be careful when using CSS and JavaScript, making sure that the browser isn’t overloaded.
- Make images smaller to lower file sizes and reduce loading times.
- On static websites, a server cache can speed up access times.
- Build a connection to external sources ahead of time to avoid bottlenecks.