Image formats across the page and the Core Web Vitals
79.7% of audited sites (157,401) serve PNG images and 73.6% serve JPEG (86% good LCP), while 38.1% serve WebP (86% good LCP) and the 11.2% adopting AVIF reach 91% good LCP (1.4s median).
11.2% of sites use AVIF images page image format mix, and 91% of those sites have a good LCP, against 86% of all sites.
LCP pass rate
Sites with AVIF images page image format mix have a good LCP most often: 91%, against 86% of all sites. Sites with other image formats image formats have it least often, at 84%.
Page image format mix usage
PNG images is the most used: 79.7% of sites. AVIF images is 11.2% of sites.
LCP phase breakdown by image formats used on the page
Across the four LCP sub-parts in Chrome's field data, the largest gap between AVIF images and other image formats sits in time to first byte (TTFB): 385 ms median for AVIF images against 613 ms for other image formats. Overall median field LCP is 1.4s for AVIF images (TTFB 385 ms, load delay 510 ms, load duration 133 ms, render delay 247 ms) versus 1.5s for other image formats.
Understanding page image formats
How AVIF and WebP across the page cut transfer weight and free bandwidth for LCP
Even when the LCP element itself is optimized, legacy PNG and JPEG assets elsewhere in the viewport compete for bandwidth on the same connection. Across 22,062 sites (11.2%) serving AVIF images, 91% pass field LCP (1.4s median). WebP is present on 38.1% of sites (86% good LCP), whereas legacy PNG (79.7%, 86% good LCP) and JPEG (73.6%, 86% good LCP) remain on four out of five pages.
Configure your image CDN or build pipeline to negotiate AVIF and WebP automatically via the Accept request header for every raster image on the page, reserving PNG and SVG strictly for logos and icons. Across all audited sites, 11.2% serve AVIF (91% good LCP, 1.4s median) and 38.1% serve WebP (86% good LCP).
How page image format mix plays out per platform
What the field data shows when you isolate a single CMS or framework.
WordPress 65,444 sites 86.6% of WordPress sites serve PNG images, 85.8% serve JPEG, and 39.0% serve WebP.
WordPress 6.5 added native AVIF upload support alongside existing WebP, JPEG, and PNG support. Across 65,444 WordPress sites, 86.6% include PNG files (75% good LCP), 85.8% include JPEGs (75% good LCP), and 39.0% include WebP (74% good LCP).
Shopify 8,567 stores Shopify serves WebP on 99.3% of storefronts and AVIF on 90.4% (97% good LCP).
Across Shopify storefronts, 99.3% serve WebP images (97% good LCP, 1.3s median) and 90.4% serve AVIF images (97% good LCP).
React & Next.js 9,561 sites React & Next.js sites serving AVIF (63.4%) pass LCP at 90% vs 74% on sites serving PNG (54.4%).
Next.js <Image> supports image/avif and image/webp output formats. Across 9,561 React sites, 63.4% serve AVIF images (90% good LCP, 1.2s median), 54.4% serve PNGs (74% good LCP, 1.7s median), and 44.6% serve JPEGs (74% good LCP).
By Arjen Karel · 210,902 crawled sites (69,745 with desktop Chrome field data, 197,455 sites with page image format mix, October 2026). How we measured.