The State of Web Vitals

Third-party share

The share of requests going to third parties.

Field data PhoneDesktopAll Scope All sites Q2 2026 edition · Phone field outcomes
Metric LCP INP CLS
1

At a glance the headline numbers for Third-party share

The share of requests going to third parties.

75.0%
on the typical site
half of sites sit at or below
75.0%
1 in 4 sites exceed this
the top quarter
93.7%
the heaviest 1%
the long tail
4,450
sites measured
phone field data

On the typical site, third parties account for 75.0% of the page.

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
2

Distribution & median CLS site count and median CLS at each level of third-party share

0.00 0.04 0.08 0.11 0.15
0.1
0 1499 2997
0 0–10 10–20 20–30 30–40 40–50 50–60 60–70 70–80 80–90 90–100 100
Good (≤0.1) Needs improvement Poor (>0.25) Site count
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
3

Passing CLS by third-party share which level passes the CLS most often

Third-party shareSitesPassing CLSCLS
0 40 89% 0.00
0–10 22 100% 0.00
10–20 44 97% 0.00
30–40 19 83% 0.00
50–60 29 93% 0.00
60–70 1,213 91% 0.00
70–80 2,997 90% 0.00
100 41 91% 0.00
Good Needs Improvement Poor Faded rows: under 100 sites

Third-party share 75.0%. p75 75.0%. p99 93.7%. Spearman with CLS r = +0.49. At the low end (0): CLS 0.00. At the high end (100): CLS 0.00. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
4

Why this matters for the Core Web Vitals, and where to start fixing it

The domain count measures connections. The third-party share measures how much of the page you do not control. Third-party script runs on the same main thread as your own code. A slow tag delays the response to every click, and that lag is your INP. Ads, embeds and consent banners inject late and shift the layout. That is CLS.

A third-party file can grow or change behaviour overnight. It never passes through your build pipeline. Your vitals move while your own code did not change. The higher the share, the more of your Core Web Vitals depends on someone else's release schedule.

How does the third-party share affect the Core Web Vitals?

Third-party share correlates with the INP. With little third-party content: 93% pass the INP. Where third parties dominate: 87%.

Go fix it The case for limiting analytics and tracking scripts → Chat widgets with perfect Core Web Vitals → Speed up a Calendly integration →
Related signals Media per page → Image format mix → Script loading mix → Iframe loading → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured