The State of Web Vitals

JS libraries impact WordPress sites

Performance impact by framework provider.

Field data PhoneDesktopAll Scope All sites October 2026 edition · Desktop field outcomes · WordPress sites only
Metric LCP INP CLS
WordPress Scoped to 63,295 sites out of 203,892 analyzed (cms) Compare with all sites →
1

At a glance the headline numbers for JS libraries impact

Performance impact by framework provider.

16
Providers ranked
After min-sites filter
120,717
Sites in sample
Combined across all items
0.07
Best CLS (p75)
Ionic
The State of Web Vitals · October 2026 · WordPress sites (63,295) · desktop field datacorewebvitals.io/state-of-cwv
2

The ranking sorted by CLS at p75, fastest first

# Provider CLS p75 Passing Sites
1 Ionic 0.07 90.5%
58
2 Stimulus/Hotwire 0.08 78.9%
53
3 Flickity 0.08 80.0%
2,957
4 GSAP 0.08 81.6%
3,245
5 Swiper 0.09 78.4%
17,874
6 Lit 0.09 77.6%
3,786
7 Lazysizes 0.10 75.7%
5,715
8 jQuery 0.10 77.2%
60,315
9 Backbone.js 0.11 74.6%
1,041
10 Moment.js 0.11 73.6%
2,772
11 Vue.js 0.11 74.5%
4,844
12 Slick Carousel 0.11 73.5%
5,156
13 Lodash 0.11 73.1%
9,344
14 Angular 0.12 70.0%
86
15 Owl Carousel 0.12 71.6%
3,371
16 React 0.17 48.4%
100
The State of Web Vitals · October 2026 · WordPress sites (63,295) · desktop field datacorewebvitals.io/state-of-cwv
3

Passing CLS per provider which group passes the CLS most often

ProviderSitesPassing CLSp75
Ionic 0.1% 58 91% 0.07
Ember.js 0.1% 49 83% 0.06
Polyfill.io 0% 18 83% 0.06
GSAP 5.1% 3,245 82% 0.08
Flickity 4.7% 2,957 80% 0.08
Stimulus/Hotwire 0.1% 53 79% 0.08
Swiper 28.2% 17,874 78% 0.09
Lit 6% 3,786 78% 0.09
jQuery 95.3% 60,315 77% 0.10
lazysizes 9% 5,715 76% 0.10
Backbone.js 1.6% 1,041 75% 0.11
Vue.js 7.7% 4,844 75% 0.11
Moment.js 4.4% 2,772 74% 0.11
Slick Carousel 8.1% 5,156 74% 0.11
Lodash 14.8% 9,344 73% 0.11
Owl Carousel 5.3% 3,371 72% 0.12
Angular 0.1% 86 70% 0.12
Next.js 0% 15 56% 0.17
React 0.2% 100 48% 0.17
Good Needs Improvement Poor Sorted best-passing first · median colored by its own rating · pass = good CLS (0.1 at p75) · one value per site

82% of GSAP sites pass CLS. React trails 34 points behind, leaving 52% of its sites failing. computed

The State of Web Vitals · October 2026 · WordPress sites (63,295) · desktop field datacorewebvitals.io/state-of-cwv
4

All five vitals at once the whole category without toggling - cell is the pass rate, small number the p75

LCP
INP
CLS
FCP
TTFB
jQuery 95.3%
752.5s
10062ms
770.10
672.0s
351.7s
Swiper 28.2%
712.7s
10063ms
780.09
632.2s
311.9s
Lodash 14.8%
652.9s
10062ms
730.11
542.5s
232.2s
lazysizes 9%
732.6s
10063ms
760.10
662.1s
321.7s
Slick Carousel 8.1%
742.6s
10062ms
740.11
662.1s
341.8s
Vue.js 7.7%
752.5s
9966ms
750.11
682.1s
351.8s
Lit 6%
712.6s
10062ms
780.09
642.1s
361.7s
Owl Carousel 5.3%
722.6s
9962ms
720.12
642.1s
331.8s
GSAP 5.1%
712.6s
10065ms
820.08
652.1s
351.7s
Flickity 4.7%
732.6s
10063ms
800.08
642.1s
311.9s
Moment.js 4.4%
642.9s
10065ms
740.11
552.5s
262.1s
Backbone.js 1.6%
752.5s
10062ms
750.11
642.1s
331.8s
React 0.2%
712.8s
10073ms
480.17
712.2s
311.7s
Angular 0.1%
852.0s
10075ms
700.12
801.6s
611.4s
Ionic 0.1%
762.4s
10068ms
910.07
482.1s
211.8s
Stimulus/Hotwire 0.1%
952.0s
9464ms
790.08
841.4s
331.1s
Ember.js 0.1%
871.7s
10064ms
830.06
831.4s
541.3s
Polyfill.io 0%
673.1s
10069ms
830.06
332.6s
01.4s
Next.js 0%
891.7s
10078ms
560.17
891.3s
561.1s
60%95%+ passing Cell: pass rate, small number = p75 · faded rows: under 100 sites

One row per provider, one column per vital - the cell is the share of sites passing, the small number the p75. No toggling needed to see where the category actually differs.

GSAP leads on CLS: 82% of its sites pass. React trails at 48%. computed

The State of Web Vitals · October 2026 · WordPress sites (63,295) · desktop field datacorewebvitals.io/state-of-cwv
Related signals A/B testing (12) → Personalization (6) → E-commerce (17) → CDN (16) → 203,892 crawled sites with Chrome field data, representing millions of real page loads · How we measured