Two in five Wix sites, 42.4%, have no iframe count per page. Of the 57.6% that do, 54% use 1 iframe, and 97% of those sites have a good CLS, against 97% of all Wix sites.
Two in five Wix sites, 42.4%, have no iframe count per page. Of the 57.6% that do, 54% use 1 iframe, and 98% of those sites have a good INP, against 96% of all Wix sites.
Two in five Wix sites, 42.4%, have no iframe count per page. Of the 57.6% that do, 54% use 1 iframe, and 94% of those sites have a good LCP, against 94% of all Wix sites.
Core Web Vitals pass rate
Sites with 1 iframe iframe count per page have a good CLS most often: 97%, against 97% of all Wix sites. Sites with 2 to 3 iframes iframe count have it least often, at 96%.
Sites with 1 iframe iframe count per page have a good INP most often: 98%, against 96% of all Wix sites. Sites with 4+ iframes iframe count have it least often, at 85%.
Sites with 1 iframe iframe count per page have a good LCP most often: 94%, against 94% of all Wix sites. Sites with 4+ iframes iframe count have it least often, at 89%.
Iframe count per page usage
Three in five Wix sites uses iframe count per page, and 54% of those use 1 iframe.
Iframe count per page per framework
On React, 42% of sites use 0 iframes iframe count per page, and 97% of React sites have a good CLS, against 97% of all sites.
On React, 42% of sites use 0 iframes iframe count per page, and 96% of React sites have a good INP, against 96% of all sites.
On React, 42% of sites use 0 iframes iframe count per page, and 94% of React sites have a good LCP, against 94% of all sites.
React 5,620 sites0 iframes 42%1 iframe 31%2 to 3 iframes 21%97%96%94%Iframe count or the framework
Does the framework explain the iframe count per page difference?
On React, 97% of sites with 1 iframe iframe count per page have a good CLS, against 99% of React sites with 0 iframes. Within React, sites with 1 iframe have a good CLS less often.
On React, 98% of sites with 1 iframe iframe count per page have a good INP, against 98% of React sites with 0 iframes. Within React, sites with 1 iframe and 0 iframes have a good INP about equally often.
On React, 94% of sites with 1 iframe iframe count per page have a good LCP, against 96% of React sites with 0 iframes. Within React, sites with 1 iframe and 0 iframes have a good LCP about equally often.
How embedded iframes destabilize layout and multiply main-thread contexts
Every <iframe> creates an independent browsing context with its own document, styles, and scripts, and frequently resizes asynchronously after load. Across 2,381 sites (42.4%) with 0 iframes, 99% pass field CLS. Adding 1 iframe (31.2%) lowers good CLS to 97%, 2 to 3 iframes (20.7%) drops good CLS to 96%, and 4 or more iframes (5.7%, 323 sites) pulls good CLS down to 96%.
Understanding iframe count
Give every iframe container a fixed CSS aspect-ratio or min-height so async frame initialization cannot shift surrounding content, add loading="lazy" to below-the-fold embeds, and replace heavy video players with static preview facades. Across all audited sites, 42.4% use 0 iframes (99% good CLS) versus 5.7% with 4+ iframes (96% good CLS).
By Arjen Karel · 5,621 crawled Wix sites (3,077 with phone Chrome field data, October 2026). How we measured.