The State of Web Vitals

WordPress CSS rendering hints and the Core Web Vitals

will-change (84.8%), aspect-ratio (67.4%), scroll-driven animations (34.7%), CSS containment (35.7%), and content-visibility (37.2%) across 51,385 sites.

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

84.8% of WordPress sites use will-change CSS rendering hints, and 100% of those sites have a good INP, against 100% of all WordPress sites.

The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 17,005 with desktop field data · 51,385 sites with CSS rendering hintsBy Arjen Karel · corewebvitals.io/state-of-cwv
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INP pass rate

Sites with will-change CSS rendering hints have a good INP most often: 100%, against 100% of all WordPress sites. Sites with CSS containment CSS hints have it least often, at 99%.

SitesGood, needs improvement, poor INPMedian
All WordPress sites17,005100%48ms
will-change 84.8%11,874100%49ms
aspect-ratio 67.4%10,061100%50ms
Scroll-driven animations 34.7%4,812100%51ms
content-visibility 37.2%5,640100%51ms
CSS contain 35.7%5,09299%51ms
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 17,005 with desktop field data · 51,385 sites with CSS rendering hintsBy Arjen Karel · corewebvitals.io/state-of-cwv
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CSS rendering hints usage

Will-change is the most used: 84.8% of WordPress sites.

Sites using each option (sites can use more than one) 51,385 sites
will-change 84.8% aspect-ratio 67.4% content-visibility 37.2% CSS contain 35.7% Scroll-driven animations 34.7%
will-change 84.8% aspect-ratio 67.4% content-visibility 37.2% CSS contain 35.7% Scroll-driven animations 34.7%
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 17,005 with desktop field data · 51,385 sites with CSS rendering hintsBy Arjen Karel · corewebvitals.io/state-of-cwv
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CSS rendering hints per framework

Vue sets the CSS rendering hints to will-change on 97% of its sites, and 99% of Vue sites have a good INP, against 100% of all sites. Alpine sets the CSS rendering hints to aspect-ratio on 86% of its sites, and 99% of Alpine sites have a good INP.

FrameworkCSS rendering hints on its sitesGood INP
WordPress sites with CSS rendering hints 51,385 siteswill-change 85%aspect-ratio 67%content-visibility 37%CSS contain 36%Scroll-driven animations 35%100%
jQuery 49,087 siteswill-change 85%aspect-ratio 67%content-visibility 38%CSS contain 36%Scroll-driven animations 35%100%
React 2,076 siteswill-change 86%aspect-ratio 84%CSS contain 55%content-visibility 48%Scroll-driven animations 45%100%
Vue 4,705 siteswill-change 97%aspect-ratio 93%Scroll-driven animations 84%content-visibility 83%CSS contain 83%99%
Alpine 336 sitesaspect-ratio 86%will-change 80%CSS contain 44%content-visibility 40%Scroll-driven animations 35%99%
will-change aspect-ratio content-visibility CSS contain Scroll-driven animations
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 17,005 with desktop field data · 51,385 sites with CSS rendering hintsBy Arjen Karel · corewebvitals.io/state-of-cwv
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CSS rendering hints or the framework

Does the framework explain the CSS rendering hints difference?

On jQuery, 100% of sites with will-change CSS rendering hints have a good INP, against 100% of jQuery sites with aspect-ratio. Within jQuery, sites with will-change and aspect-ratio have a good INP about equally often. On Vue, 100% of sites with will-change CSS rendering hints have a good INP, against 99% of Vue sites with aspect-ratio. Within Vue, sites with will-change and aspect-ratio have a good INP about equally often.

How CSS rendering hints isolate layout and compositor work

CSS hints instruct the rendering engine how to allocate compositor layers and skip offscreen layout work. Among hint-using sites, 84.8% use will-change (100% good INP), 67.4% use aspect-ratio (100% good INP), 34.7% use scroll-driven animations (100% good INP), 35.7% use contain (99% good INP), and 37.2% use content-visibility (100% good INP).

The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 17,005 with desktop field data · 51,385 sites with CSS rendering hintsBy Arjen Karel · corewebvitals.io/state-of-cwv
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Understanding CSS rendering hints

Use aspect-ratio to reserve responsive media boxes, scroll-driven animations to move scroll effects off the main thread, and content-visibility: auto with contain-intrinsic-size on long below-the-fold sections. Avoid applying will-change across large numbers of elements, which exhausts GPU memory.

Go fix it Fix excessive DOM size → HTML reflow and Core Web Vitals → INP: presentation delay →
The State of Web Vitals · October 2026 · WordPress: 63,295 crawled sites · 17,005 with desktop field data · 51,385 sites with CSS rendering hintsBy Arjen Karel · corewebvitals.io/state-of-cwv
Related signals Scheduling API use → Interaction invoker types → Yielding strategy → INP phase breakdown → By Arjen Karel · 63,295 crawled WordPress sites (17,005 with desktop Chrome field data, 51,385 sites with CSS rendering hints, October 2026) · How we measured