v148 · HTML · Performance
Lazy Gallery
A media gallery with 12 video and audio elements, all marked loading="lazy". Scroll down to see each item load as it enters the viewport. A live counter shows how many have loaded vs. are still deferred, saving bandwidth for items the user never reaches.
Click "Generate gallery" to create lazy-loaded media items, then scroll to watch them load.
The markup
<!-- Chrome 148: loading="lazy" on <video> -->
<video loading="lazy" controls src="/media/demo.mp4"></video>
<!-- Chrome 148: loading="lazy" on <audio> -->
<audio loading="lazy" controls src="/media/demo.mp3"></audio>
<!-- Eager (always loads immediately) -->
<video loading="eager" controls src="/media/hero.mp4"></video>
<!-- Default is "eager" if omitted —
lazy only activates when attribute is present -->
references
implementation reference
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