The State of Web Vitals

DOM depth

The deepest nesting level in the DOM tree.

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

At a glance the headline numbers for DOM depth

The deepest nesting level in the DOM tree.

18
on the typical site
half of sites sit at or below
23
1 in 4 sites exceed this
the top quarter
41
the heaviest 1%
the long tail
180,899
sites measured
desktop field data

The typical DOM tree is 18 levels deep.

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

Distribution & median CLS site count and median CLS at each level of DOM depth

0.00 0.04 0.08 0.11 0.15
0.1
0 10602 21204
11–11 12–12 13–13 14–14 15–15 16–16 17–17 18–18 19–19 20–20 21–21 22–22 23–23 24–24 25–25 26–26 27+
Good (≤0.1) Needs improvement Poor (>0.25) Site count
The State of Web Vitals · Q2 2026 · 189,915 sites · desktop field datacorewebvitals.io/state-of-cwv
3

Passing CLS by DOM depth which level passes the CLS most often

DOM depthSitesPassing CLSCLS
11–11 5,873 82% 0.02
12–12 8,679 82% 0.02
13–13 9,084 82% 0.02
14–14 10,746 80% 0.02
15–15 11,379 78% 0.03
16–16 11,657 79% 0.03
17–17 11,772 78% 0.03
18–18 11,898 78% 0.03
19–19 10,246 77% 0.03
20–20 9,518 76% 0.03
21–21 8,365 75% 0.03
22–22 9,548 75% 0.03
23–23 8,487 77% 0.03
24–24 6,480 75% 0.04
25–25 5,920 74% 0.04
26–26 4,135 73% 0.04
27+ 21,204 74% 0.04
Good Needs Improvement Poor Faded rows: under 100 sites

DOM depth 18. p75 23. p99 41. At the low end (11–11): CLS 0.02. At the high end (27+): CLS 0.04. computed

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

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

Depth is a different problem than size. Styles inherit downwards. Toggle a class high in the tree and the browser recalculates everything below it. Layout changes also travel through ancestors, and percentage heights and flexbox make that worse. Selector matching walks the ancestor chain too, so deep trees pay more for every CSS rule.

In practice this shows up as INP. The click is fast and the JavaScript is fast, but the style and layout pass after the update is slow because the change affects too many nested levels. A flatter tree holds the same content but keeps each update local.

Go fix it Fix excessive DOM size →
Related signals Script coverage (used vs unused) → Image loading attribute → Images per page → Compression mix → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured