The State of Web Vitals

DOM depth

The deepest nesting level in the DOM tree.

Field data PhoneDesktopAll Scope All sites Q1 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
94,748
sites measured
desktop field data

The typical DOM tree is 18 levels deep.

The State of Web Vitals · Q1 2026 · 94,910 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 16491 32982
0 1 2 3 4 5–6 7–9 10–13 14–18 19–26 27–37 >p98
Good (≤0.1) Needs improvement Poor (>0.25) Site count
The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
3

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

DOM depthSitesPassing CLSCLS
1 217 82% 0.01
2 904 80% 0.01
3 303 82% 0.01
4 259 83% 0.02
5–6 877 83% 0.01
7–9 3,241 85% 0.01
10–13 14,769 83% 0.02
14–18 30,165 79% 0.03
19–26 32,982 76% 0.03
27–37 9,399 73% 0.04
>p98 1,631 78% 0.02
Good Needs Improvement Poor Faded rows: under 100 sites

DOM depth 18. p75 23. p99 41. At the low end (1): CLS 0.01. At the high end (>p98): CLS 0.02. computed

The State of Web Vitals · Q1 2026 · 94,910 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.

How does DOM depth affect the Core Web Vitals?

Passing INP barely moves across the range: 97% at one end, 97% at the other. This signal does not separate passing sites from failing ones.

The effect is bigger on LCP. In the flattest trees, 85% of sites pass it. In the deepest trees, 77% do.

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 94,910 sites, representing millions of real page loads · How we measured