Wix speculation rules posture and the Core Web Vitals

Sites with prefetch speculation rules pass all three Core Web Vitals most often: 89%, against 89% of all Wix sites. The biggest gap is LCP, 95% against 94%.

Sites with prefetch speculation rules have a good LCP most often: 95%, against 94% of all Wix sites. Sites with prerender-until-script speculation rules have it least often, at 93%.

Sites with prerender-until-script speculation rules have a good INP most often: 98%, against 96% of all Wix sites. Sites with prefetch speculation rules have it least often, at 96%.

Sites with prefetch speculation rules have a good CLS most often: 98%, against 97% of all Wix sites. Sites with prerender-until-script speculation rules have it least often, at 97%.

99.2% of Wix sites use speculation rules, and nine in ten of those use prefetch.

React sets the speculation rules to prefetch on 90% of its sites, and 89% of React sites pass all three Core Web Vitals, against 89% of all sites.

React sets the speculation rules to prefetch on 90% of its sites, and 94% of React sites have a good LCP, against 94% of all sites.

React sets the speculation rules to prefetch on 90% of its sites, and 96% of React sites have a good INP, against 96% of all sites.

React sets the speculation rules to prefetch on 90% of its sites, and 97% of React sites have a good CLS, against 97% of all sites.

FrameworkSpeculation rules on its sitesPass all three

All Wix sites 5,621 sitesPrefetch 90%89%

React 5,620 sitesPrefetch 90%89%

Prefetch Prerender until script No rules

Does the framework explain the speculation rules difference?

On React, 89% of sites with prefetch speculation rules pass all three Core Web Vitals, against 88% of React sites with prerender-until-script. Within React, sites with prefetch and prerender-until-script pass all three about equally often.

On React, 95% of sites with prefetch speculation rules have a good LCP, against 93% of React sites with prerender-until-script. Within React, sites with prefetch and prerender-until-script have a good LCP about equally often.

On React, 98% of sites with prerender-until-script speculation rules have a good INP, against 96% of React sites with prefetch. Within React, sites with prerender-until-script and prefetch have a good INP about equally often.

On React, 98% of sites with prefetch speculation rules have a good CLS, against 97% of React sites with prerender-until-script. Within React, sites with prefetch and prerender-until-script have a good CLS about equally often.

How prefetch, prerender-until-script, and prerender differ in Chrome

A prefetch rule only downloads the next page's HTML document ahead of the click, removing network TTFB on the subsequent navigation while leaving subresources and rendering until after the visitor navigates. A prerender-until-script rule downloads the HTML and subresources and builds the DOM and CSSOM in a hidden renderer, pausing before JavaScript executes. A full prerender rule executes scripts and paints the next page in the background so activation is near-instant.