100.0% of Wix sites use Last-Modified headers Last-Modified cache validation, and 94% of those sites have a good LCP, against 94% of all Wix sites.
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 5,333 with all devices field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
Sites with Last-Modified headers Last-Modified cache validation have a good LCP most often: 94%, against 94% of all Wix sites.
SitesGood, needs improvement, poor LCPMedian
All Wix sites5,33394%1.2s
Last-Modified present 100.0%5,33394%1.2s
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 5,333 with all devices field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
2
Last-Modified cache validation usage
Last-Modified headers is the most used: 100.0% of Wix sites.
Last-Modified present 100.0%
Last-Modified present 100.0%
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 5,333 with all devices field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
3
LCP phase breakdown for sites with and without Last-Modified headers
Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
All Wix sites 3,945419 ms455 ms137 ms151 ms455 mslab 455 ms1.2s
Last-Modified present 3,945419 ms455 ms137 ms151 ms455 mslab 455 ms1.2s
TTFB Resource load delay Resource load time Element render delay
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 5,333 with all devices field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
4
Last-Modified cache validation per framework
React sets the Last-Modified cache validation to Last-Modified headers on 100% of its sites, and 94% of React sites have a good LCP, against 94% of all sites.
FrameworkLast-Modified cache validation on its sitesGood LCP
All Wix sites 5,621 sitesLast-Modified present 100%94%
React 5,620 sitesLast-Modified present 100%94% Last-Modified present
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 5,333 with all devices field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
5
Last-Modified headers or the framework
Does the framework explain the Last-Modified cache validation difference?
Almost every site with Last-Modified headers Last-Modified cache validation is a React site, and almost every React site has Last-Modified headers Last-Modified cache validation, so the data can't tell Last-Modified headers Last-Modified cache validation and React apart.
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 5,333 with all devices field dataBy Arjen Karel · corewebvitals.io/state-of-cwv