Best Image Formats for Web in 2023

Choosing the right image format is crucial for reducing file size while maintaining quality. This guide will help you understand which formats work best for different types of images and use cases.

Modern Image Formats

WebP

WebP is a modern image format developed by Google that provides superior lossless and lossy compression for web images.

• Advantages: 25-35% smaller file sizes compared to JPEG at equivalent quality; supports transparency
• Best for: Photos, graphics, and images with transparency
• Browser support: Excellent (Chrome, Firefox, Safari, Edge)
• Size reduction: Up to 35% smaller than JPEG, 45% smaller than PNG

AVIF

AVIF (AV1 Image File Format) is the newest format with exceptional compression efficiency.

• Advantages: Superior compression; maintains high quality at very low file sizes
• Best for: Photos and complex images where maximum compression is needed
• Browser support: Growing (Chrome, Firefox, Opera)
• Size reduction: Up to 50% smaller than WebP, 80% smaller than JPEG

Traditional Image Formats

JPEG/JPG

JPEG remains the most widely used format for photographs on the web.

• Advantages: Universal compatibility; good compression for photos
• Best for: Photographs and images with many colors and gradients
• Limitations: Lossy compression; no transparency support
• Optimization tips: Use quality settings between 70-85% for web

PNG

PNG is ideal for images that require transparency or have sharp edges.

• Advantages: Lossless compression; transparency support
• Best for: Logos, icons, screenshots, and images with text
• Limitations: Larger file sizes for photographs
• Types: PNG-8 (256 colors) and PNG-24 (millions of colors)

SVG

SVG is a vector format that's perfect for logos, icons, and simple illustrations.

• Advantages: Scalable to any size without quality loss; small file size for simple graphics
• Best for: Logos, icons, and simple illustrations
• Limitations: Not suitable for photographs
• Optimization tips: Minimize path points; remove unnecessary metadata

Format Comparison for Reducing Image Size

Recommendations for Different Use Cases

For Photographs

1. AVIF (if browser support is not a concern)
2. WebP (best balance of compression and compatibility)
3. JPEG (for maximum compatibility)

For Graphics with Transparency

1. WebP (best balance of quality and file size)
2. PNG-8 (if limited colors are acceptable)
3. PNG-24 (if high color fidelity is required)

For Logos and Icons

1. SVG (ideal for simple, vector-based graphics)
2. WebP (for complex logos with many colors)
3. PNG (for maximum compatibility)

Implementing a Modern Image Strategy

For the best balance of quality and performance, consider implementing a responsive image strategy:

• Use the <picture> element to provide multiple formats
• Serve AVIF or WebP to modern browsers, with JPEG/PNG fallbacks
• Provide different image sizes for different devices
• Use lazy loading for images below the fold