JPEG / WebP / AVIF

What Are JPEG, WebP, and AVIF?

The choice of image format directly impacts your Core Web Vitals and therefore your rankings: switching from JPEG to WebP or AVIF can reduce file size by 25–50% without visible quality loss. Especially on mobile devices where bandwidth and battery life matter, this difference is noticeable. The transition is one of the easiest and most effective performance optimizations you can implement.

JPEG, WebP, and AVIF are three image formats with different compression rates and quality characteristics that affect SEO. JPEG is the oldest and most widely used format but offers the worst compression; WebP is a modern format developed by Google with better compression and quality; AVIF is the newest format with even better efficiency. For search engine optimization, the choice of the right image format is relevant because it significantly influences page load time — and load time is a direct ranking factor.

The mechanism differs in compression: JPEG uses lossy compression and can cause visible quality loss at high compression. WebP uses more advanced compression and is about 25–35% smaller than JPEG at equal quality. AVIF is even more efficient — about 20–30% smaller than WebP. This means faster downloads, less data usage, and improved page speed metrics. Browser support was previously a problem (older browsers didn’t recognize WebP/AVIF), but has improved significantly.

In practice, website owners should optimize their image formats: use AVIF where browser support is sufficient; use WebP as the standard format for modern users; use JPEG only as a fallback for older browsers; and replace old, large JPEG files with modern formats. Modern CMS and image optimization tools offer automatic conversion. Picture tags and srcset in HTML allow different browsers to automatically receive the best format. This is a demonstrably effective measure for improving Core Web Vitals and thus rankings.