How to Optimize Images for Web Performance in 2025

Images typically account for 50-75% of a web page's total size. Optimizing them is the single most impactful thing you can do for page speed.

Key Metrics

Largest Contentful Paint (LCP): Often determined by your hero image

Cumulative Layout Shift (CLS): Prevented by setting image dimensions

Total page weight: Directly affected by image sizes

1. Choose the right format: WebP for photos, SVG for icons, PNG for transparency

2. Compress aggressively: Use quality 80-85% for JPEG/WebP

3. Resize to display dimensions: Don't serve 4000px images in 800px containers

4. Use responsive images: Serve different sizes for different viewports

5. Lazy load below-fold images: Only load images when they're about to enter the viewport

6. Use CDN: Serve images from edge locations close to users

Image Compressor for batch compression

Image Resizer for exact dimensions

Format Converter for WebP conversion

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