Definition
Preload is a browser hint that tells it to fetch an important resource as early as possible during the current page load, rather than waiting until it is discovered naturally. It is used for things the page needs right away, such as a key font, a hero image, or a critical script. This moves vital files to the front of the queue.
Use Cases
Preload is used to remove delays for resources that are essential to the first view of a page, so visitors do not see missing fonts or blank spaces. It is most helpful for files the browser would otherwise find late, deep inside the code.
Why It Matters for SEO
Preload matters for SEO because loading critical resources sooner improves page speed metrics like Largest Contentful Paint, which Google measures. It works alongside hints such as preconnect to shape the order in which a page comes together. Used only for truly important files, it makes the first view appear faster.
Related Concepts
Related concepts include preconnect, prefetch, and HTML rendering. They are all ways of telling the browser what to prioritize so the page is ready sooner.