Optimizing Images for Web Performance: A Complete Guide

Why Image Optimization Matters

Images typically account for 50-70% of a webpage's total weight. Optimizing them is one of the most impactful things you can do to improve your site's performance.

The Core Principles

1. Choose the Right Format

**WebP**: Best overall choice, 25-35% smaller than JPEG

**AVIF**: Even better compression, but less browser support

**JPEG**: Good for photographs when WebP isn't an option

**PNG**: Use for images requiring transparency

**SVG**: Perfect for icons and simple graphics

2. Serve the Right Size

Never serve a 4000px image when 800px will do. Use responsive images:

<img

srcset="image-400.webp 400w,

image-800.webp 800w,

image-1200.webp 1200w"

sizes="(max-width: 600px) 400px,

(max-width: 1200px) 800px,

1200px"

src="image-800.webp"

alt="Description"

3. Compress Intelligently

Quality settings of 75-85% for JPEG/WebP usually provide the best balance between file size and visual quality.

Tools We Recommend

**Our Image Optimizer** at apps.exlac.com - Fast, easy, and free

**Squoosh** - Google's browser-based tool

**ImageOptim** - Desktop app for Mac

**Sharp** - Node.js library for automation

Advanced Techniques

**Lazy loading**: Only load images when they enter the viewport

**Blur-up placeholders**: Show a tiny blurred version while loading

**CDN delivery**: Serve images from edge locations close to users

Conclusion

Image optimization isn't optional—it's essential for a good user experience. Start with the basics and progressively implement more advanced techniques as needed.