Lazy Loading for Video & Audio in Chrome

Extending the existing loading attribute from images to media elements.

Status: ✅ Landed in Chromium (CL 7511253 merged Feb 20, 2026)

Shipping in Chrome 148

The feature landed default-enabled and is expected in Chrome 148 stable.

The corresponding HTML specification and Web Platform Tests are merged.

The Gap

Since 2019, we've had this:

<img src="photo.jpg" loading="lazy">

But not this:

<video src="hero.mp4" loading="lazy">  <!-- Nope -->
<audio src="podcast.mp3" loading="lazy">  <!-- Nope -->

Media elements did not have the equivalent behavior until this change.

Why It Matters

Think about:

Podcast platforms - lists of audio players
E-commerce - product videos below the fold
Landing pages - media in sections that begin outside the viewport
Documentation - embedded tutorial videos

All of these eagerly load every media file upfront. Bandwidth wasted on content users might never scroll to.

The Effort

This isn't a solo project. Scott Jehl and the Squarespace team have been driving a proper cross-browser standardization effort:

HTML Spec proposal written and submitted
Firefox patch in review
WebKit patch ready
Web Platform Tests contributed for the shared behavior
Mozilla has an official positive standards position

When Yoav Weiss posted in Chromium Slack that they needed someone for the Chrome side, I figured the Firefox patch and WPTs would make it straightforward to port. They did.

WPTs passing in patched Chromium

The Behavior

<video loading="lazy" poster="thumb.jpg" autoplay muted>
  <source src="video.mp4" type="video/mp4">
  <track src="captions.vtt" kind="subtitles">
</video>

What	When `loading="lazy"`
Video/audio source	Waits for viewport
Poster image	Waits for viewport
Track elements (captions)	Waits for viewport
Autoplay	Queued until visible

Changes from lazy to eager? Triggers immediate load.

The implementation reuses Chromium's existing lazy load infrastructure—same intersection observer as images, same network-aware margins.

Status

Browser	Patch	Standards Position
Chromium	MERGED CL 7511253	POSITIVE
Firefox	IN REVIEW D278547	POSITIVE
WebKit	Ready (not submitted)	PENDING