Choosing the right image format is crucial for web performance. WebP and JPEG are two of the most popular formats, but which one should you use? This comprehensive comparison breaks down the differences to help you make an informed decision.
Key Takeaway: WebP typically offers 25-35% smaller file sizes than JPEG at equivalent quality, with support for transparency and animation. However, JPEG maintains nearly universal browser compatibility.
Compression Efficiency
WebP consistently outperforms JPEG in compression efficiency:
- Lossy Compression: WebP images are 25-34% smaller than JPEGs at equivalent SSIM quality index
- Lossless Compression: WebP lossless images are 26% smaller than PNGs
- Visual Quality: At high compression levels, WebP maintains better detail with fewer artifacts
| Format | Avg. File Size | Quality Score | Features |
|---|---|---|---|
| WebP | 65-75KB | 95 (SSIM) | Transparency, Animation |
| JPEG | 90-100KB | 95 (SSIM) | Wide Compatibility |
Browser Support
JPEG has near-universal support across all browsers and devices. WebP support is extensive but not complete:
- WebP Supported: Chrome, Firefox, Edge, Opera (all versions), Safari 14+
- WebP Not Supported: Internet Explorer, Safari 13 and below
- Fallback Strategy: Use <picture> element with WebP as first source and JPEG as fallback
When to Use Each Format
Use WebP when:
- Your audience uses modern browsers (95%+ of users in 2023)
- You need transparency support (without PNG filesize)
- Page load performance is critical
- You can implement fallback for unsupported browsers
Use JPEG when:
- You need maximum compatibility (legacy systems)
- Your CMS doesn't support WebP conversion
- You're distributing images for offline use
Conversion Recommendations
For optimal results when converting JPEG to WebP:
- Start with the highest quality source available
- Use quality setting between 75-85 for WebP (equivalent to JPEG 70-80)
- Test multiple settings to find the best quality/filesize balance
- Implement proper caching headers for WebP images
Pro Tip: For WordPress users, plugins like Imagify or ShortPixel can automatically serve WebP to supported browsers while falling back to JPEG for others.