What is WebP?
WebP is an image format introduced by Google in 2010, specifically designed for the web. As the name suggests — "Web Picture". It combines lossy (like JPG) and lossless (like PNG) compression in a single format, adding transparency and animation on top.
WebP's Three Superpowers
- Significantly smaller files: Averaging 25-35% smaller than JPG, 50-80% smaller than PNG.
- Transparency + Animation: PNG's transparency plus GIF's animation, in one format.
- 96%+ browser support: Chrome, Firefox, Safari, Edge — all support it. Works everywhere except IE 11 and old Safari.
Site Speed: Why It Matters
Google's ranking algorithm considers Core Web Vitals as an important factor. If a page's LCP (Largest Contentful Paint) exceeds 2.5 seconds, SEO performance drops. The biggest LCP killer: large images waiting to load.
A typical e-commerce product page has 8-12 images. Converting each to WebP can reduce total page size by 40-60%. This drops a 5-second LCP on 3G mobile to 2 seconds.
WebP's Downsides
No technology is perfect. WebP has weak points too:
- Professional tool support: Photoshop only got native WebP support in 2022. Older tools require plugins.
- Software compatibility: WordPress 5.8+ supports it, but some older themes/plugins still expect JPG/PNG.
- SEO fallback: Some bots still don't index WebP. The safest approach is providing JPG fallback via the
<picture>tag.
How to Migrate to WebP
Three practical paths:
- Online converter: Bulk convert your existing JPG/PNG files with JPG → WebP or PNG → WebP.
- CMS plugin: "WebP Express" for WordPress, built-in support for Shopify.
- Auto-CDN: CDNs like Cloudflare and Bunny.net offer "Polish" that auto-generates WebP on upload.
Picture Tag Fallback
Fallback is essential for older browsers. The HTML5 <picture> tag handles this elegantly:
<picture>
<source srcset="image.webp" type="image/webp">
<img src="image.jpg" alt="Description">
</picture>If the browser supports WebP, it loads that; if not, it falls back to JPG. No JS required.
Conclusion
WebP has become the standard for modern websites. If you still use JPG/PNG, just by converting images to WebP you can improve page speed by 1-2 seconds. This directly benefits both UX and SEO.