The State of Web Vitals

Connection hints

dns-prefetch, preconnect and preload links the document declares.

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

At a glance the headline numbers for Connection hints

dns-prefetch, preconnect and preload links the document declares.

0
dns-prefetch hints
on the typical page
0
preconnect hints
on the typical page
0
preloads
on the typical page
180,684
sites measured
phone field data

Connection hints on the typical site: 0 dns-prefetch, 0 preconnect, 0 preload.

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 connection hints — dns prefetch

0.00 0.04 0.08 0.11 0.15
0.1
0 61373 122745
0 1 2 3 4 5 6 7 8–9 >p98
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 connection hints — dns prefetch which level passes the CLS most often

Connection hints — dns prefetchSitesPassing CLSCLS
0 122,745 89% 0.00
1 27,801 90% 0.00
2 13,338 89% 0.00
3 6,538 87% 0.00
4 4,231 90% 0.00
5 2,088 90% 0.00
6 1,084 87% 0.00
7 667 89% 0.00
8–9 1,150 89% 0.00
>p98 1,042 82% 0.01
Good Needs Improvement Poor Faded rows: under 100 sites

Connection hints — dns prefetch 0. p75 1. p99 8. Spearman with CLS r = +0.34. At the low end (0): CLS 0.00. At the high end (>p98): CLS 0.01. computed

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

Distribution & median CLS site count and median CLS at each level of connection hints — preconnect

0.00 0.04 0.08 0.11 0.15
0.1
0 64781 129562
0 1 2 3 4 5 6 7 >p98
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
5

Passing CLS by connection hints — preconnect which level passes the CLS most often

Connection hints — preconnectSitesPassing CLSCLS
0 129,562 89% 0.00
1 19,644 87% 0.00
2 17,172 90% 0.00
3 7,180 89% 0.00
4 3,810 86% 0.00
5 1,484 75% 0.01
6 622 81% 0.01
7 420 84% 0.01
>p98 790 78% 0.03
Good Needs Improvement Poor Faded rows: under 100 sites

Connection hints — preconnect 0. p75 1. p99 6. Spearman with CLS r = +0.39. At the low end (0): CLS 0.00. At the high end (>p98): CLS 0.03. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
6

Distribution & median CLS site count and median CLS at each level of connection hints — preload

0.00 0.04 0.08 0.11 0.15
0.1
0 64187 128374
0 1 2 3 4 5 6–7 8–10 11–13 14–18 19–25 >p98
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
7

Passing CLS by connection hints — preload which level passes the CLS most often

Connection hints — preloadSitesPassing CLSCLS
0 128,374 89% 0.00
1 14,607 88% 0.00
2 10,628 89% 0.00
3 4,694 87% 0.00
4 6,925 91% 0.00
5 4,215 90% 0.00
6–7 4,466 87% 0.00
8–10 2,745 80% 0.00
11–13 1,318 85% 0.00
14–18 930 83% 0.00
19–25 775 82% 0.01
>p98 1,007 78% 0.01
Good Needs Improvement Poor Faded rows: under 100 sites

Connection hints — preload 0. p75 1. p99 18. Spearman with CLS r = +0.36. At the low end (0): CLS 0.00. At the high end (>p98): CLS 0.01. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
8

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

Hints move network work earlier. dns-prefetch resolves a domain name before it is needed. preconnect goes further and completes the TCP and TLS setup too. preload fetches one specific file that the scanner would otherwise find late, like a background hero image or a critical font.

Hints are easy to overuse. Every preconnect spends sockets and CPU on a connection you might never use. A preload that is not critical steals bandwidth from something that is. A handful of deliberate hints beats a wall of them.

How does this affect the Core Web Vitals?

Connection hints correlate with the LCP. Preloads separates passing sites from failing sites the most. With few preloads, 81% of sites pass the LCP. With many, 63% do. The decline is gradual. There is no point where sites suddenly start failing.

Go fix it Guide to resource prioritization → Preload the LCP image → When preloading stylesheets does not make sense → 103 Early Hints →
Related signals Cacheable responses → Last-Modified present → Requests via CDN → HTML size (kB) → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured