The State of Web Vitals

HTML document size on Wix sites

2.5% of audited sites (140) ship an initial HTML document under 14 KB and reach 95% good LCP (1.2s median), compared to 0% good LCP (3.3s median) on the <0.1% shipping 30 to 75 KB of HTML.

Field data PhoneDesktopAll Scope All sites October 2026 edition · All devices field outcomes · Wix sites only
Wix Scoped to 5,623 sites out of 203,892 analyzed (cms) Compare with all sites →
LCP Loading INP Interaction

2.5% of Wix sites use under 14 KB of HTML initial HTML document size, and 95% 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
1

Core Web Vitals pass rate

Sites with under 14 KB of HTML initial HTML document size have a good LCP most often: 95%, against 94% of all Wix sites. Sites with over 75 KB of HTML HTML size have it least often, at 94%.

SitesGood, needs improvement, poor LCPMedian
All Wix sites5,33394%1.2s
Under 14 KB (First TCP window) 2.5%13595%1.2s
Over 75 KB 97.5%5,19794%1.2s
30 KB to 75 KB <0.1%10%3.3s
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

Initial HTML document size usage

Over 75 KB of HTML is the most used: 97.5% of Wix sites. Under 14 KB of HTML is 2.5% of Wix sites.

Over 75 KB 97.5%
Over 75 KB 97.5% Under 14 KB (First TCP window) 2.5% 30 KB to 75 KB <0.1%
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 by initial HTML document size

Across the four LCP sub-parts in Chrome's field data, the largest gap between under 14 KB of HTML and over 75 KB of HTML sits in resource load delay: 415 ms median for under 14 KB of HTML against 456 ms for over 75 KB of HTML. Overall median field LCP is 1.2s for under 14 KB of HTML (TTFB 418 ms, load delay 415 ms, load duration 132 ms, render delay 151 ms) versus 1.2s for over 75 KB of HTML.

Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
All Wix sites 3,945455 mslab 455 ms1.2s
Under 14 KB (First TCP window) 98415 mslab 415 ms1.2s
Over 75 KB 3,846456 mslab 456 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

Initial HTML document size per framework

On React, 97% of sites use over 75 KB of HTML initial HTML document size, and 94% of React sites have a good LCP, against 94% of all sites.

FrameworkInitial HTML document size on its sitesGood LCP
All Wix sites 5,621 sitesOver 75 KB 97%94%
React 5,620 sitesOver 75 KB 97%94%
Over 75 KB Under 14 KB (First TCP window) 30 KB to 75 KB
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

HTML document size or the framework

Does the framework explain the initial HTML document size difference?

On React, 95% of sites with under 14 KB of HTML initial HTML document size have a good LCP, against 94% of React sites with over 75 KB of HTML. Within React, sites with under 14 KB of HTML and over 75 KB of HTML have a good LCP about equally often.

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
6

Understanding initial HTML document size

Place <meta charset>, viewport, and <link rel="preload"> for the LCP image at the very top of <head> within the first 14 KB, and trim oversized inline CSS blocks or serialized SSR JSON payloads. Across all audited sites, 2.5% ship under 14 KB (95% good LCP) while <0.1% ship 30 to 75 KB (0% good LCP).

Go fix it Preload the LCP image → Eliminate render-blocking resources → 103 Early Hints →
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
Related signals HTTP protocol mix → HTTP protocol → ETag present → Cache strategy mix → By Arjen Karel · 5,621 crawled Wix sites (5,333 with all devices Chrome field data, October 2026) · How we measured