Improve Core Web Vitals with Better Image Optimization

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Practical tactics to reduce LCP, prevent layout shifts and improve INP using responsive, compressed and properly served images.

1. Map image metrics

  • LCP → hero / large media above the fold.
  • CLS → dimensionless media shifting flow.
  • INP → heavy decode / main-thread blocking.

2. Reduce LCP

  • Preload hero image (<link rel="preload" as="image">).
  • Compress (modern format + proper quality).
  • Serve exact display dimension or responsive srcset.

3. Prevent CLS

  • Always add width & height (or CSS aspect-ratio).
  • Avoid late-loading banners pushing content.
  • Reserve space for ad / dynamic placeholders.

4. Optimize INP impact

  • Defer non-critical below-the-fold images via lazy loading.
  • Use decoding="async" where supported.
  • Strip EXIF / ICC if not needed.

5. Delivery tactics

  • Use CDN with smart caching.
  • Serve AVIF/WebP fallback chain.
  • Use HTTP/2 / 3 + compression.

6. Monitoring

  • Field data (CrUX, RUM) over lab only.
  • Track hero resource timing & size budgets.
  • Alert on regression thresholds.

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FAQ

  • How do images affect LCP?
    Large, unoptimized hero images delay first render of the largest element; reduce bytes and use proper dimensions.
  • How to reduce CLS from images?
    Always include width & height or aspect-ratio so space is reserved before load.

Count of local transformations you do here (convert, optimize, resize, crop, remove background). All done privately in your browser.