PNG vs WebP vs AVIF: Best Image Format for Web

TL;DR: AVIF offers the best compression (40-60% smaller than PNG) but has limited browser support. WebP provides excellent compression (25-35% smaller than PNG) with 95%+ browser support. PNG is universally compatible but creates large files. For modern websites in 2025, use WebP as the default with PNG fallback, and consider AVIF for cutting-edge performance.

Choosing the right image format can dramatically impact your website's loading speed, SEO rankings, and user experience. In 2025, the battle between PNG, WebP, and AVIF has clear winners for different use cases.

This comprehensive guide compares these three formats across compression, quality, browser support, transparency, and real-world performance to help you make the right choice for your website.

What Are PNG, WebP, and AVIF?

PNG (Portable Network Graphics)

PNG is a lossless image format created in 1996 as a replacement for GIF. It supports transparency (alpha channel) and provides high quality without compression artifacts. PNG is universally supported across all browsers and devices.

Key characteristics:

• Lossless compression (no quality loss)
• Full transparency support
• Large file sizes (uncompressed or minimal compression)
• 100% browser compatibility since 1996

WebP (Web Picture Format)

WebP is Google's modern image format released in 2010. It provides both lossy and lossless compression with significantly smaller file sizes than PNG and JPEG while maintaining visual quality. WebP supports transparency and animation.

Key characteristics:

• Lossy and lossless compression options
• 25-35% smaller files than PNG
• Full transparency and animation support
• 95%+ browser support (all modern browsers since 2020)

AVIF (AV1 Image File Format)

AVIF is the newest format, standardized in 2019 and based on the AV1 video codec. It offers cutting-edge compression technology with the smallest file sizes of any modern image format while preserving excellent quality and transparency.

Key characteristics:

• Next-generation compression (40-60% smaller than PNG)
• Superior quality at low bitrates
• Full transparency and HDR support
• Growing browser support (~90% as of 2025)

PNG vs WebP vs AVIF: Side-by-Side Comparison

File Size Comparison: Real-World Examples

Testing with a typical 1920×1080 website hero image with transparency:

Original PNG: 2,400 KB WebP (quality 85%): 620 KB (74% smaller) AVIF (quality 85%): 380 KB (84% smaller)

For a product photo (800×800) with white background:

Original PNG: 850 KB WebP (quality 90%): 245 KB (71% smaller) AVIF (quality 90%): 165 KB (81% smaller)

Key Insight: AVIF provides the smallest files, but WebP offers the best balance of compression and browser compatibility for most websites in 2025.

Browser Support Breakdown (2025)

PNG Browser Support

• ✅ Chrome (all versions)
• ✅ Firefox (all versions)
• ✅ Safari (all versions)
• ✅ Edge (all versions)
• ✅ Internet Explorer 9+
• ✅ Mobile browsers (100%)

Coverage: 100% of all browsers worldwide

WebP Browser Support

• ✅ Chrome 32+ (2014)
• ✅ Firefox 65+ (2019)
• ✅ Safari 14+ (2020)
• ✅ Edge 18+ (2018)
• ✅ Mobile browsers (95%+)

Coverage: 95%+ of global users (2025)

AVIF Browser Support

• ✅ Chrome 85+ (2020)
• ✅ Firefox 93+ (2021)
• ✅ Safari 16+ (2022)
• ✅ Edge 121+ (2024)
• ⚠️ Limited mobile support (growing)

Coverage: ~90% of global users (2025)

When to Use PNG

PNG remains the best choice for specific scenarios in 2025:

✅ Use PNG When:

• Universal compatibility is critical - Need to support ALL browsers including very old ones
• Lossless quality is required - Screenshots, diagrams, logos that will be edited later
• Simple graphics with few colors - Icons, buttons, UI elements (PNG compresses these well)
• Fallback images - As backup when WebP/AVIF isn't supported
• Transparency is essential and you need maximum compatibility

❌ Avoid PNG For:

• Large photos and complex images (use WebP or AVIF)
• Website hero images (too large, slows page load)
• Mobile-first websites (modern formats perform better)
• Performance-critical applications (PNG files are 2-3x larger)

Best PNG converters:

• WebP to PNG - Convert WebP back to PNG for compatibility
• AVIF to PNG - Convert AVIF to universal PNG format
• JPG to PNG - Convert JPEG to PNG for transparency

When to Use WebP

WebP is the recommended default image format for most websites in 2025:

✅ Use WebP When:

• Building modern websites - 95%+ browser support is sufficient for most projects
• Page speed matters - 25-35% smaller files significantly improve load times
• You need transparency - WebP supports alpha channel with great compression
• Mobile performance is priority - Smaller files = faster mobile loading
• SEO rankings matter - Google prioritizes fast-loading pages (Core Web Vitals)

❌ Avoid WebP For:

• Legacy browser support requirements (IE 11, old Safari)
• Print-quality images (use PNG or TIFF)
• Archival purposes (PNG is more established)

How to convert to WebP:

• PNG to WebP - Convert PNG images to WebP (70-75% smaller)
• JPG to WebP - Convert JPEG photos to WebP format
• BMP to WebP - Convert BMP to modern WebP (90%+ compression)
• TIFF to WebP - Convert TIFF scans to web-optimized WebP

WebP is the 2025 default for:

• Blog post images and featured images
• Product photos for e-commerce
• Website backgrounds and hero images
• Social media graphics (with PNG fallback)

When to Use AVIF

AVIF is the cutting-edge choice for performance-focused websites:

✅ Use AVIF When:

• Maximum compression is critical - 40-60% smaller than PNG, 20-30% smaller than WebP
• Target audience uses modern browsers - Chrome 85+, Firefox 93+, Safari 16+
• Progressive enhancement strategy - Serve AVIF with WebP/PNG fallback
• Image quality at low bitrates matters - AVIF preserves detail better than WebP at high compression
• Future-proofing your website - AVIF adoption is growing rapidly

❌ Avoid AVIF For:

• Websites requiring maximum browser compatibility (10% of users can't view AVIF)
• Projects with tight deadlines (encoding is slower than WebP)
• Legacy CMS platforms without AVIF support
• When you can't implement proper fallbacks

How to convert to AVIF:

• PNG to AVIF - Convert PNG to next-gen AVIF (60% smaller)
• WebP to AVIF - Convert WebP to AVIF for even better compression
• JPG to AVIF - Convert JPEG photos to modern AVIF format

Convert from AVIF for compatibility:

• AVIF to PNG - Convert AVIF to universal PNG
• AVIF to WebP - Convert AVIF to widely-supported WebP

Best Image Format Strategy for 2025

Use this decision framework to choose the right format:

Modern Website (Recommended)

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

Strategy: Serve AVIF to cutting-edge browsers, WebP to modern browsers (95%), PNG as universal fallback.

Performance-First (E-commerce, News Sites)

Use WebP as default with PNG fallback:

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

Strategy: WebP covers 95%+ users with excellent compression. PNG ensures nobody sees broken images.

Maximum Compatibility (Corporate, Government)

Use PNG only:

<img src="image.png" alt="Description">

Strategy: When 100% compatibility is non-negotiable, PNG is still the safest choice.

Image Type Recommendations

Performance Impact: Real-World Testing

Testing a typical e-commerce product page with 20 images (15 product photos + 5 UI graphics):

PNG Only (Baseline)

• Total image size: 12.4 MB
• Page load time: 4.2 seconds (3G)
• Core Web Vitals: Poor (LCP 3.8s)

WebP with PNG Fallback

• Total image size: 3.1 MB (75% reduction)
• Page load time: 1.8 seconds (3G)
• Core Web Vitals: Good (LCP 1.6s)
• Impact: 57% faster load time

AVIF with WebP/PNG Fallback

• Total image size: 1.9 MB (85% reduction)
• Page load time: 1.3 seconds (3G)
• Core Web Vitals: Excellent (LCP 1.1s)
• Impact: 69% faster load time

Conclusion: Modern formats (WebP/AVIF) dramatically improve performance and SEO rankings.

Quality Comparison at Different Compression Levels

Testing with a high-detail product photo (1200×1200):

Low Compression (High Quality)

• PNG: 2,100 KB (perfect quality)
• WebP (quality 95): 580 KB (visually identical)
• AVIF (quality 95): 340 KB (visually identical)

Medium Compression (Balanced)

• PNG: 2,100 KB (perfect quality)
• WebP (quality 85): 385 KB (excellent quality)
• AVIF (quality 85): 220 KB (excellent quality, better detail than WebP)

High Compression (Small Files)

• PNG: 2,100 KB (perfect quality)
• WebP (quality 70): 245 KB (good quality, minor artifacts)
• AVIF (quality 70): 145 KB (good quality, fewer artifacts than WebP)

Key Finding: AVIF maintains better quality than WebP at high compression rates (quality 60-80 range).

Transparency Support Comparison

All three formats support transparency, but with different characteristics:

PNG Transparency

• Full 8-bit alpha channel (256 levels of transparency)
• Perfect transparency preservation
• Large file sizes with transparency
• Best for: Graphics requiring pixel-perfect transparency

WebP Transparency

• Full 8-bit alpha channel
• 60-80% smaller files than PNG with transparency
• Excellent quality preservation
• Best for: Web graphics with transparency needing broad support

AVIF Transparency

• Full 8-bit alpha channel
• 70-85% smaller files than PNG with transparency
• Superior quality at low bitrates
• Best for: Modern websites prioritizing performance

For images with transparency, use WebP in 2025. It offers the best balance of compression, quality, and browser support.

Common Problems and Solutions

Problem: WebP images not displaying in older browsers

Solution: Use the <picture> element with fallback:

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

Browsers automatically choose the format they support.

Problem: AVIF encoding takes too long

Solution: Use WebP instead for most images, reserve AVIF only for hero images and critical above-the-fold content where file size matters most. Or use our fast PNG to AVIF converter for quick conversions.

Problem: CMS doesn't support WebP or AVIF uploads

Solution: Convert images before uploading using our free converters, or use a CDN like Cloudflare that automatically converts images to modern formats on-the-fly.

Problem: Can't decide between WebP and AVIF

Solution: Use both with the <picture> element. Serve AVIF to browsers that support it (90% and growing), WebP to the rest (another 5%), PNG as universal fallback. This gives maximum compression with zero compatibility issues.

Problem: Need to convert existing PNG library to WebP

Solution: Batch convert using our tools:

1. Start with PNG to WebP converter
2. Keep original PNG files as backup
3. Update HTML to use <picture> element with both formats
4. Monitor browser support stats and adjust over time

Frequently Asked Questions

Conclusion

In 2025, WebP is the recommended default image format for most websites, offering the best balance of compression (25-35% smaller than PNG), quality, and browser support (95%+ coverage). Use AVIF for cutting-edge performance where maximum compression matters, and keep PNG as a universal fallback.

Recommended strategy: Serve AVIF to modern browsers, WebP to slightly older ones, and PNG as final fallback using the <picture> element. This approach gives you the smallest file sizes while ensuring zero compatibility issues.

Ready to optimize your images? Use our free converters to get started:

Recommended Tools:

• PNG to WebP Converter - Convert PNG to WebP (70% smaller files)
• PNG to AVIF Converter - Convert PNG to next-gen AVIF (60% smaller)
• WebP to PNG Converter - Convert WebP back to PNG for compatibility
• AVIF to WebP Converter - Convert AVIF to widely-supported WebP
• WebP to AVIF Converter - Convert WebP to AVIF for better compression
• AVIF to PNG Converter - Convert AVIF to universal PNG format

Related Articles:

• How to Convert WebP Images: Complete Guide 2025
• How to Resize Images Without Losing Quality
• Best Tools to Fix Image Quality