WebP vs AVIF — Image Format Comparison
Choosing between WebP and AVIF for your website images impacts page speed, SEO, and user experience. This guide compares both next-generation image formats across all key dimensions. Use our Image Converter to convert between formats.
Quick Overview
Feature | WebP | AVIF ─────────────────────┼──────────────────────────────┼────────────────────────────── Developer | Google | Alliance for Open Media Release Year | 2010 | 2019 Compression | Good (25-35% smaller than JP) | Best (50% smaller than JPEG) Lossy Support | Yes | Yes Lossless Support | Yes | Yes Transparency (Alpha) | Yes | Yes Animation | Yes (animated WebP) | Yes (AVIS) Browser Support | 97% | 80% Encoding Speed | Fast | Slow (2-5x WebP) Decoding Speed | Fast | Moderate HDR Support | No | Yes Wide Color Gamut | No | Yes
File Size Comparison
At equivalent visual quality (SSIM), AVIF consistently produces smaller files than WebP. Testing shows AVIF files are typically 20-30% smaller than WebP at the same quality setting, and up to 50% smaller than JPEG.
Format | File Size | Size vs JPEG | Quality ────────┼───────────┼──────────────┼───────── JPEG | 100 KB | — | Good WebP | 65 KB | -35% | Same visual quality AVIF | 45 KB | -55% | Same visual quality
Browser Support
Browser support is the most important practical consideration. WebP is supported in all modern browsers, covering 97% of global users. AVIF covers about 80% with support in Chrome, Firefox, and Opera — Safari added AVIF support in version 16.4.
<!-- Use picture element for fallback support --> <picture> <source srcset="image.avif" type="image/avif"> <source srcset="image.webp" type="image/webp"> <img src="image.jpg" alt="Fallback"> </picture>
When to Use Each Format
Use WebP When
You need broad browser compatibility, fast encoding for dynamic image generation, animated images (alternative to GIF), and photos where 25-35% size reduction over JPEG is sufficient.
Use AVIF When
Maximum compression is critical (slow networks, data-limited plans), you serve primarily to Chrome/Firefox users, static assets where encoding speed is not a concern, and you need HDR or wide color gamut support.
Encoding Speed Considerations
AVIF encoding is significantly slower than WebP — typically 2-5x slower depending on settings. For static assets this is acceptable, but for real-time image processing or server-side dynamic conversion, WebP's faster encoding is a practical advantage.