Lazy Loading

What is Lazy Loading?

Especially on image-heavy pages like online stores or portfolios, lazy loading can cut initial loading time in half. This directly improves your Core Web Vitals and therefore your Google rankings. Important note: images in the immediately visible area must not be lazy-loaded, or your LCP score will suffer.

Lazy loading is a technique where images and other media content are not loaded immediately on page load, but only when the user scrolls to them. This method significantly improves the initial load time of a page, since fewer resources need to be downloaded upfront. For content-heavy websites and long pages with many images, lazy loading is an effective tool for optimizing Core Web Vitals, especially Largest Contentful Paint (LCP).

Technically, lazy loading is implemented through the native HTML attribute loading=“lazy” or through JavaScript libraries. The native attribute is simpler and supported by all modern browsers — you simply add it to img and iframe tags. The browser then loads the image only when it’s close to the visible area. This not only saves bandwidth but also reduces initial rendering time and improves crawl efficiency. A page with 30 images becomes significantly faster through lazy loading if only 5–8 of them are loaded immediately.

When implementing, keep in mind that images in the above-the-fold area (the immediately visible portion) must not be lazy-loaded, as this worsens LCP. Only images placed below the fold should be lazy-loaded. Also ensure that lazy loading doesn’t impair Google image search — structured data and alt texts must be present for lazy-loaded images too. Properly implemented, lazy loading is one of the most effective techniques for improving page speed, which translates measurably into better rankings.