Image Optimization for Core Web Vitals: Faster Page Speeds
Actionable techniques to optimize Largest Contentful Paint (LCP) and Cumulative Layout Shift (CLS) through smart image formatting.
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Google's Core Web Vitals ranking algorithm heavily penalizes websites with slow loading hero images and unexpected layout shifts.
1. Optimize Largest Contentful Paint (LCP)
- Ensure hero banners are properly compressed into WebP or optimized JPEG.
- Avoid lazy-loading your primary LCP hero image (add `fetchpriority="high"` instead).
2. Eliminate Cumulative Layout Shift (CLS)
- Always set explicit `width` and `height` attributes on HTML `<img>` elements so the browser reserves the correct aspect-ratio box before the image finishes downloading.
- Inline tiny critical icons as Base64 Data URIs to eliminate render-blocking network requests.
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