How to Pass Google PageSpeed Image Audits — Every Optimization Explained

Common PageSpeed Image Warnings

"Serve images in next-gen formats"

Problem: Using JPEG or PNG instead of WebP or AVIF. Fix: Convert images to WebP format. Use a bulk converter for existing images.

"Properly size images"

Problem: Serving a 2000px image that displays at 400px. Fix: Resize images to their display dimensions. Create srcset with multiple sizes.

"Efficiently encode images"

Problem: Images not compressed enough. Fix: Compress JPEG to quality 75-85%, WebP to quality 75-80%.

"Defer offscreen images"

Problem: Below-fold images loading during initial page load. Fix: Add loading="lazy" to images below the fold.

"Serve images with appropriate resolution"

Problem: Not serving 2x images for retina displays. Fix: Create 1x and 2x versions, use srcset.

The Complete Fix Process

1. Audit: Run PageSpeed Insights and note all image warnings
2. Convert: Batch convert to WebP
3. Resize: Batch resize to display dimensions (plus 2x versions)
4. Compress: Quality 75-80% for WebP, 80-85% for JPEG
5. Implement: Add srcset, sizes, loading="lazy"
6. Re-test: Run PageSpeed again to verify improvements

Expected Score Improvements

Starting Score	After Image Optimization
30-50	60-80
50-70	75-90
70-85	85-98

Image optimization alone can improve PageSpeed scores by 15-30 points.