Does WordPress Lazy Load Images by Default?
How Core's Lazy Loading Works
WordPress automatically adds the browser-native loading="lazy" attribute to eligible images (generally those below the immediately visible area, since the very first visible image benefits from loading immediately rather than being delayed). This relies on native browser support rather than a JavaScript library, making it lightweight and requiring no additional plugin for the basic functionality most sites need.
Things Worth Knowing
- The very first, immediately visible image on a page (often the featured image or a hero image) is deliberately excluded from lazy loading by core's own logic, since delaying the most visually prominent, immediately-seen element would actually hurt perceived load speed.
- Some page builder or slider plugins implement their own lazy-loading logic that can occasionally conflict with core's native behavior, worth checking if images inside those specific components behave unexpectedly.
- Lazy loading can be disabled via a filter for specific images or sitewide, if a particular situation genuinely calls for it, though this is rarely necessary given the sensible default behavior.
- This is distinct from lazy-loading other resource types (videos, iframes), which may need separate, plugin-based handling if not natively supported the same way.
Confirming This Works Well
- No action is usually needed, since this is enabled automatically by core.
- Check for conflicts if a specific page builder or slider's images seem to have loading issues, since a plugin's own lazy-loading logic occasionally clashes with core's.
- Confirm the above-the-fold image loads immediately rather than being delayed, which would hurt perceived speed.
Need image loading performance investigated for a specific issue? See WordPress speed optimization.