WebP and AVIF are image formats that deliver smaller file sizes than JPEG and PNG at equivalent visual quality. For WordPress sites, that means faster page loads, lower bandwidth costs, and better Core Web Vitals — specifically Largest Contentful Paint (LCP), which is directly affected by image delivery speed.
WebP vs. AVIF: What's the Difference?
WebP was developed by Google and is supported by all major browsers. It reduces JPEG file sizes by 25–35% at equivalent quality. For most WordPress sites, WebP is the right default output format.
AVIF is newer and achieves even better compression — often 40–50% smaller than JPEG. Browser support is strong on modern versions. The practical approach: generate both, serve AVIF to browsers that support it, fall back to WebP for others.
Even a well-compressed JPEG is larger than a well-compressed WebP at the same quality. Format conversion compounds savings from compression. A 500KB JPEG → 350KB compressed → 220KB as WebP. That's a 56% total reduction.
What WordPress Needs to Serve WebP and AVIF
WordPress doesn't generate WebP or AVIF itself — that's handled by plugins. When a plugin generates a WebP version, browsers that support it receive the smaller file automatically. WordPress 5.8+ includes native serving support via the <picture> element when a plugin provides the converted file.
How to Enable WebP and AVIF in WordPress
- Install NaveenCodes Image Optimizer from WordPress.org
- Go to Image Optimizer → Settings
- Enable Generate WebP and optionally Generate AVIF
- Choose a compression preset (Balanced recommended for most sites)
- Run Bulk Optimize to convert your existing Media Library
- New uploads are handled automatically going forward
Does Enabling WebP Break Anything?
No. WebP conversion creates additional files alongside your originals — it doesn't replace them. If a browser doesn't support WebP, it receives the original JPEG or PNG. The same applies to AVIF. Both formats are served conditionally based on browser support.
FAQ
Do all browsers support WebP?
Yes. Chrome, Firefox, Safari (since macOS 11), Edge, and all major mobile browsers support WebP. It's safe as a default output format.
Is AVIF better than WebP?
AVIF generally achieves better compression than WebP, but browser support is slightly less universal. Generating both and serving based on support gives you the best of both formats.
Will converting to WebP improve my Google PageSpeed score?
Yes. Google PageSpeed and Lighthouse explicitly recommend serving images in next-gen formats. Converting to WebP is one of the highest-impact optimizations available.
Enable WebP and AVIF. Free.
NaveenCodes Image Optimizer generates WebP and AVIF on upload and in bulk. Free on WordPress.org. No credit limits.