WordPress total CSS payload and the Core Web Vitals

13.3% of audited sites (8,364) ship under 40 KB of CSS and pass LCP at 85% (1.5s median), whereas the 35.8% shipping over 160 KB drop to 58% (2.3s median).

Field data PhoneDesktopAll Scope All sites October 2026 edition · All devices field outcomes · WordPress sites only
WordPress Scoped to 63,295 sites out of 203,892 analyzed (cms) Compare with all sites →

13.3% of WordPress sites use under 40 KB of CSS total CSS payload, and 85% of those sites have a good LCP, against 70% of all WordPress sites.

The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
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LCP pass rate

Sites with under 40 KB of CSS total CSS payload have a good LCP most often: 85%, against 70% of all WordPress sites. Sites with over 160 KB of CSS CSS payload have it least often, at 58%.

SitesGood, needs improvement, poor LCPMedian
All WordPress sites60,85570%1.9s
Under 40 KB 13.3%8,00885%1.5s
40 to 80 KB 20.6%12,40079%1.7s
80 to 160 KB 30.3%18,29571%1.9s
Over 160 KB 35.8%21,65858%2.3s
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
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Total CSS payload usage

Over 160 KB of CSS is the most used: 35.8% of WordPress sites. Under 40 KB of CSS is 13.3% of WordPress sites.

Over 160 KB 35.8% 80 to 160 KB 30.3% 40 to 80 KB 20.6% Under 40 KB 13.3%
Over 160 KB 35.8% 80 to 160 KB 30.3% 40 to 80 KB 20.6% Under 40 KB 13.3%
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
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The four LCP phases

Across the four LCP sub-parts in Chrome's field data, the largest gap between under 40 KB of CSS and over 160 KB of CSS sits in time to first byte (TTFB): 839 ms median for under 40 KB of CSS against 1335 ms for over 160 KB of CSS. Overall median field LCP is 1.5s for under 40 KB of CSS (TTFB 839 ms, load delay 221 ms, load duration 156 ms, render delay 214 ms) versus 2.3s for over 160 KB of CSS.

Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
WordPress sites with total CSS payload 43,2751129 ms341 ms341 mslab 341 ms1.9s
Under 40 KB 5,475839 ms221 mslab 221 ms1.5s
40 to 80 KB 8,730994 ms285 ms285 mslab 285 ms1.7s
80 to 160 KB 13,2041139 ms343 ms343 mslab 343 ms1.9s
Over 160 KB 15,8661335 ms431 ms252 ms431 mslab 431 ms2.3s
TTFB Resource load delay Resource load time Element render delay
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
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Total CSS payload per framework

On jQuery, 36% of sites use over 160 KB of CSS total CSS payload, and 69% of jQuery sites have a good LCP, against 70% of all sites. On Vue, 43% of sites use over 160 KB of CSS, and 68% of Vue sites have a good LCP.

FrameworkTotal CSS payload on its sitesGood LCP
WordPress sites with total CSS payload 62,783 sitesOver 160 KB 36%80 to 160 KB 30%40 to 80 KB 21%Under 40 KB 13%70%
Alpine 377 sitesUnder 40 KB 29%40 to 80 KB 26%80 to 160 KB 24%Over 160 KB 21%80%
jQuery 59,843 sitesOver 160 KB 36%80 to 160 KB 31%40 to 80 KB 21%Under 40 KB 12%69%
Vue 4,835 sitesOver 160 KB 43%80 to 160 KB 32%40 to 80 KB 16%68%
React 2,211 sitesOver 160 KB 49%80 to 160 KB 31%40 to 80 KB 12%61%
Over 160 KB 80 to 160 KB 40 to 80 KB Under 40 KB
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
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Total CSS payload or the framework

Does the framework explain the total CSS payload difference?

On jQuery, 84% of sites with under 40 KB of CSS total CSS payload have a good LCP, against 57% of jQuery sites with over 160 KB of CSS. Within jQuery, sites with under 40 KB of CSS have a good LCP more often. On Vue, 82% of sites with under 40 KB of CSS total CSS payload have a good LCP, against 57% of Vue sites with over 160 KB of CSS. Within Vue, sites with under 40 KB of CSS have a good LCP more often.

Why stylesheet weight is a direct render blocker

External stylesheets block first paint until every CSS file in the document head is downloaded and parsed into the CSSOM. Across 8,364 sites (13.3%) under 40 KB of CSS, 85% pass field LCP at a 1.5s median, while the 35.8% (22,448) exceeding 160 KB fall to 58% good LCP (2.3s median).

The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
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Understanding total CSS payload

Enable per-block stylesheet loading in WordPress and replace monolithic page-builder or FontAwesome CSS files with inline critical CSS. On WordPress, 13.3% of sites ship under 40 KB of CSS (85% good LCP) while 35.8% exceed 160 KB (58% good LCP).

The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 60,855 with all devices field data · 62,783 sites with total CSS payloadBy Arjen Karel · corewebvitals.io/state-of-cwv
Related signals Script loading mix → Font source → Image format mix → Iframe loading → By Arjen Karel · 63,295 crawled WordPress sites (60,855 with all devices Chrome field data, 62,783 sites with total CSS payload, October 2026) · How we measured