Image File Formats Explained - JPG vs PNG vs WebP vs AVIF

Implementation Steps:

• Use HTML picture element with multiple sources
• Order sources from most modern to most compatible
• Include WebP, then JPG/PNG fallbacks
• Test across different browsers and devices

Code Example:

<picture>
  <source srcset="image.avif" type="image/avif">
  <source srcset="image.webp" type="image/webp">
  <img src="image.jpg" alt="Description">
</picture>

Implementation Steps:

• Check Accept header for format support
• Use CDN or server logic to choose format
• Cache different versions efficiently
• Monitor performance and adjust strategy

Code Example:

// Server detects WebP support
if (req.headers.accept.includes('image/webp')) {
  return 'image.webp';
} else {
  return 'image.jpg';
}

Implementation Steps:

• Load images only when needed
• Choose format based on viewport and connection
• Prioritize above-the-fold images
• Use intersection observer for optimal timing

Code Example:

// Lazy load with format selection
const observer = new IntersectionObserver((entries) => {
  entries.forEach(entry => {
    if (entry.isIntersecting) {
      loadOptimalFormat(entry.target);
    }
  });
});