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
all-device field data
The typical DOM tree is 18 levels deep.
The State of Web Vitals · Q2 2026 · 189,915 sites · all devices field datacorewebvitals.io/state-of-cwv
2
Distribution & median LCP site count and median LCP at each level of DOM depth
0ms 750ms 1500ms 2250ms 3000ms
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 (≤2.5s) Needs improvement Poor (>4s) Site count
The State of Web Vitals · Q2 2026 · 189,915 sites · all devices field datacorewebvitals.io/state-of-cwv
3
Passing LCP by DOM depth which level passes the LCP most often
DOM depthSitesPassing LCPLCP
11–11 5,873 91% 1.2s
12–12 8,679 90% 1.3s
13–13 9,084 89% 1.3s
14–14 10,746 88% 1.4s
15–15 11,379 87% 1.4s
16–16 11,657 86% 1.4s
17–17 11,772 83% 1.5s
18–18 11,898 83% 1.6s
19–19 10,246 82% 1.6s
20–20 9,518 79% 1.6s
21–21 8,365 78% 1.7s
22–22 9,548 78% 1.7s
23–23 8,487 78% 1.7s
24–24 6,480 73% 1.8s
25–25 5,920 74% 1.8s
26–26 4,135 73% 1.8s
27+ 21,204 77% 1.7s
Good Needs Improvement Poor Faded rows: under 100 sites
DOM depth 18. p75 23. p99 41. At the low end (11–11): LCP 1.2s. At the high end (27+): LCP 1.7s. computed
The State of Web Vitals · Q2 2026 · 189,915 sites · all devices 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.
Chrome field data from 189,915 sites, representing millions of real page loads. How we measured.