Responsive Images and Media with AI Optimization
Images account for the majority of page weight on most websites, making responsive image handling critical for both performance and user experience. This lesson covers the technical implementation of responsive images using HTML5 features, plus modern AI tools that can automatically resize, compress, and optimize images for every device and connection speed.
Watch: Video Walkthrough
Key Concepts
- srcset and sizes: Letting the browser choose the optimal image resolution
- Picture Element: Art direction for different screen sizes and formats
- Modern Formats: WebP and AVIF for dramatically smaller file sizes
- AI Image Tools: Using Cloudinary, imgix, and Squoosh for automated optimization
Hands-On Exercise
Task: Take a hero image and create a complete responsive image solution: generate 4 different sizes (400w, 800w, 1200w, 1600w), convert to WebP format, and implement using the picture element with appropriate srcset and sizes attributes. Measure the page weight reduction compared to a single full-size image.
Pro Tips
Use the loading="lazy" attribute on all images below the fold, but never on the first visible image (it delays LCP). Combine lazy loading with responsive images for the best performance: the browser loads only the right size, and only when needed.