The State of Web Vitals

First-party vs third-party scripts on React sites

99.9% of audited sites (9,568) execute first-party scripts (99% good INP, 48ms median), while 94.7% (9,059) also execute third-party scripts from external origins (99% good INP, 49ms median).

Field data PhoneDesktopAll Scope All sites October 2026 edition · Desktop field outcomes · React sites only
React Scoped to 9,570 sites out of 210,902 analyzed (frameworks) Compare with all sites →
INP Interaction LCP Loading

94.7% of React sites use third-party scripts script origin (first-party vs third-party), and 99% of those sites have a good INP, against 99% of all React sites.

The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
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Core Web Vitals pass rate

Sites with third-party scripts script origin (first-party vs third-party) have a good INP most often: 99%, against 99% of all React sites. Sites with first-party scripts script origin have it least often, at 99%.

SitesGood, needs improvement, poor INPMedian
All React sites1,97999%48ms
Third-party scripts 94.7%1,89799%49ms
First-party scripts 99.9%1,97999%48ms
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
2

Script origin (first-party vs third-party) usage

First-party scripts is the most used: 99.9% of React sites. Third-party scripts is 94.7% of React sites.

Sites using each option (sites can use more than one) 9,570 sites
First-party scripts 99.9% Third-party scripts 94.7%
First-party scripts 99.9% Third-party scripts 94.7%
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
3

Script origin (first-party vs third-party) per platform

Wix sets the script origin (first-party vs third-party) to third-party scripts on 100% of its sites, and 100% of Wix sites have a good INP, against 99% of all sites. WordPress sets the script origin (first-party vs third-party) to first-party scripts on 100% of its sites, and 100% of WordPress sites have a good INP.

PlatformScript origin (first-party vs third-party) on its sitesGood INP
All React sites 9,570 sitesFirst-party scripts 100%Third-party scripts 95%99%
Wix 5,824 sitesFirst-party scripts 100%Third-party scripts 100%100%
WordPress 2,342 sitesFirst-party scripts 100%Third-party scripts 83%100%
First-party scripts Third-party scripts
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
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Script origin or the platform

Does the platform explain the script origin (first-party vs third-party) difference?

On Wix, 100% of sites with third-party scripts script origin (first-party vs third-party) have a good INP, against 100% of Wix sites with first-party scripts. Within Wix, sites with third-party scripts and first-party scripts have a good INP about equally often. On WordPress, 100% of sites with third-party scripts script origin (first-party vs third-party) have a good INP, against 100% of WordPress sites with first-party scripts. Within WordPress, sites with third-party scripts and first-party scripts have a good INP about equally often.

How external third-party scripts compete with first-party interactivity

First-party scripts execute on 99.9% of audited sites (9,568, 99% good INP at a 48ms median). Four out of five sites (94.7%, 9,059) also load third-party scripts from external domains (99% good INP, 49ms median), adding unscheduled timer callbacks, event listeners, and long tasks to the shared browser main thread.

The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
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Understanding first-party vs third-party scripts

Audit external <script> origins regularly, remove unused marketing tags, and move analytics collection to server-side endpoints or Web Workers so third-party scripts do not block user interactions. Across all audited sites, 99.9% run first-party scripts (48ms median INP) and 94.7% run third-party scripts (49ms median INP).

Go fix it The case for limiting analytics and tracking scripts → Defer scripts until needed → Chat widgets with perfect Core Web Vitals →
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
Related signals Script initiator → Image dimensions set → Scripts per page → Stylesheets per page → By Arjen Karel · 9,570 crawled React sites (1,979 with desktop Chrome field data, October 2026) · How we measured