AVIF vs WebP vs JPEG: Which one actually wins?

A 2MB JPEG drops to 480KB in WebP and plummets to 310KB in AVIF while maintaining the same visual quality. I've spent the last couple of weeks building an image compression tool and processed thousands of files, so I decided to run a real-world benchmark using 100 assets (50 vacation/product photos and 50 UI screenshots) to see where the actual breaking points are.

The Performance Breakdown

I tested these against original files ranging from 500KB to 12MB. To keep the comparison fair, I used settings that look identical on a 2x retina display: JPEG (q85), WebP (q80), and AVIF (q65).

• JPEG (q85): Avg size 820 KB. Baseline.
• WebP (q80): Avg size 480 KB. Roughly 41.5% smaller than JPEG.
• AVIF (q65): Avg size 310 KB. Roughly 62.2% smaller than JPEG.

For standard photography, AVIF is the clear winner for payload. On a typical product page with six images, switching from JPEG to AVIF reduces the page weight by about 3MB. On a 10 Mbps connection, that's the difference between a 4-second load and a 1.5-second load.

Graphics and Screenshots

PNGs behave differently. If you need pixel-perfect accuracy for text-heavy screenshots, lossless PNG compression is still the safest bet. However, for UI mockups or illustrations:

• Original PNG: 1.4 MB
• Lossless PNG: 640 KB
• WebP (q80): 180 KB (Visually identical, not pixel-perfect)
• AVIF (q65): 120 KB (Similar visual quality to WebP)

The Trade-off: Encoding Latency

The massive file size savings of AVIF come with a heavy compute cost. AVIF is significantly slower to encode than the alternatives:

• JPEG: 0.3s per image
• WebP: 0.8s per image
• AVIF: 2.5s per image

If you are running a static site generator, encoding at build time is a non-issue. But for platforms handling massive amounts of user-generated content in real-time, WebP is the practical sweet spot.

Implementation Strategy

For e-commerce or high-traffic sites, the most efficient AI workflow for image delivery is using the <picture> element to serve AVIF to the 93% of browsers that support it, with a WebP fallback.

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

For general blogging, just sticking with WebP at 80% quality provides the best balance of compatibility and speed without the encoding overhead of AVIF.