WebP Format — Why It Outperforms JPEG and PNG

Why WebP Is the Modern Image Format

WebP is an image format developed by Google that provides both lossy and lossless compression in a single format. It consistently achieves 25-35% smaller file sizes compared to JPEG at equivalent quality, and up to 26% smaller than PNG for lossless images.

Key Advantages

1. Superior Compression: WebP lossy images are typically 25-34% smaller than JPEG at the same SSIM (Structural Similarity Index) quality score.

2. Transparency Support: Unlike JPEG, WebP supports alpha channel transparency. A WebP image with transparency is typically 3x smaller than a PNG with the same transparency.

3. Animation Support: WebP supports animation (like GIF) but with much better compression. Animated WebP files are 64% smaller than equivalent GIF animations.

4. Both Lossy and Lossless: A single format handles both use cases, simplifying your image pipeline.

Browser Support (2025)

Browser	Lossy WebP	Lossless WebP	Animated WebP
Chrome 17+	Yes	Yes	Yes
Firefox 65+	Yes	Yes	Yes
Safari 14+	Yes	Yes	Yes
Edge 18+	Yes	Yes	Yes

As of 2025, WebP is supported by over 97% of browsers worldwide.

When NOT to Use WebP

• When you need to support very old browsers (IE11)
• When compatibility with desktop image editors matters (some older tools cannot open WebP)
• When you need CMYK color space (print workflows)

Migration Strategy

The most common approach is to serve WebP with JPEG/PNG fallbacks using the <picture> element:

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