Image Compression

Why It Matters

Unoptimized images are the #1 cause of slow page speeds, accounting for 50-70% of page weight. Proper compression improves Core Web Vitals scores, page speed (1-3 second improvement typical), mobile performance, and user experience. Every 1-second speed improvement increases conversions by 7%.

How It Works

Compression removes unnecessary data from image files using lossy (some quality loss, smaller files) or lossless (no quality loss, larger files) methods. Modern formats like WebP and AVIF provide 25-35% better compression than JPEG/PNG. Automated tools can compress images during upload or build processes.

Use Cases

• An e-commerce site converts all product photos from PNG to WebP, reducing page load time from 5.2s to 1.8s
• A photography portfolio compresses high-res images from 5MB to 200KB each while maintaining visual quality
• A news site implements automatic compression on upload, ensuring all images load quickly on mobile networks

Best Practices

• Use modern image formats: WebP for photos/graphics, AVIF for cutting-edge compression, SVG for logos
• Target file sizes: under 100KB for hero images, 50KB for product photos, 20KB for thumbnails
• Use lossy compression at 75-85% quality - most users can't see the difference from 100%
• Implement responsive images with srcset to serve appropriate sizes for different devices
• Automate compression in your build process or CMS to ensure consistency
• Test compressed images on actual devices to ensure quality meets standards