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Lazy loading

Lazy loading is an optimization strategy where content that is not immediately visible to the user—typically images and videos "below the fold"—is deferred and only loaded as the user scrolls down the page and approaches it. This technique improves initial page load times by reducing the number of resources the browser needs to download and render upfront, and it also conserves bandwidth for the user. The simplest native method is to add the loading="lazy" attribute to an img tag. It is critical, however, to never apply lazy loading to images that are visible in the initial viewport, especially the Largest Contentful Paint (LCP) element, as this would delay its discovery and negatively impact performance.

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Fabian Krumbholz
Fabian Krumbholz
April 8, 20261 min read

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