Why Image Optimization Matters
Images account for 50% or more of a typical webpage's total weight. Optimizing images is often the single biggest improvement you can make to page performance.
Modern Image Formats
WebP offers 25-35% smaller file sizes than JPEG. AVIF offers even better compression, up to 50% smaller than JPEG, with excellent quality.
Image Optimization Techniques
1
Use Modern Formats with Fallbacks
Use <picture> element to serve AVIF/WebP with JPEG fallback for older browsers.
2
Implement Responsive Images
Use srcset and sizes attributes to serve appropriately sized images for each viewport.
3
Lazy Load Below-the-Fold Images
Use loading='lazy' attribute for images not visible on initial page load.
4
Set Explicit Dimensions
Always include width and height attributes to prevent layout shifts.