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Lazy Loading

Lazy Loading Performance

Practice testing lazy-loaded content and performance metrics. Scroll down to trigger image loading.

LOADED
0/20
NETWORK REQUESTS
0
BANDWIDTH SAVED
0 KB
DEFERRED
20

How Lazy Loading Works

Images are only loaded when they enter the viewport. Scroll down to see more images load. Check the Network tab in DevTools to observe the requests.

Image Gallery (Scroll to load)

Image 1
Image 2
Image 3
Image 4
Image 5
Image 6
Image 7
Image 8
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Image 10
Image 11
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Image 13
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Image 15
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Image 20

Automation Tips

  • Scroll Simulation: Use scrollIntoView() or page.evaluate(() => window.scrollTo(...))
  • Load Detection: Wait for data-loaded="true" attribute on lazy elements
  • Network Monitoring: Use CDP to monitor network requests during scroll
  • Performance API: Access window.performance.getEntriesByType('resource')