The State of Web Vitals

Script loading mix

How scripts load: parser-blocking, async, defer, module or inline.

Field data PhoneDesktopAll Scope All sites Q1 2026 edition · Desktop field outcomes
Metric LCP INP CLS
1

At a glance the headline numbers for Script loading mix

How scripts load: parser-blocking, async, defer, module or inline.

7
Categories
In the distribution
40.6%
Fleet share
Top: inline
94.2%
Sites with any
Of inline

8.1% of scripts still block the parser.

The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
2

The script loading mix mix who uses what, and how fast each group loads

Median INP (sites using feature)
0
100ms
200ms
300ms
400ms
500ms
Inline49ms41% of sites
Async50ms21% of sites
Other48ms20% of sites
Defer52ms9% of sites
Blocking48ms8% of sites
Module57ms2% of sites
Nomodule59ms0% of sites
VariantShare of requestsMedian
Inline
41%
49ms
Async
21%
50ms
Other
20%
48ms
Defer
9%
52ms
Blocking
8%
48ms
Module
2%
57ms
Nomodule
0%
59ms

Script loading mix. On the fleet: 40.6% inline, 21.1% async, 19.8% other. 94.2% of sites use at least one inline.

By count inline leads (40.6%); by bytes it is async (50.1%). computed

The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
3

Passing INP per bucket every category and count level at once - color is the pass rate

1
2
3
4
5
6
7
8
9
10
11
Inline 40.6%
99
99
99
99
99
99
99
99
99
99
98
Async 21.1%
99
100
100
99
99
99
99
98
99
98
98
Other 19.8%
99
99
99
100
98
99
99
100
100
99
100
Defer 8.6%
99
99
99
99
99
99
99
99
99
99
99
Blocking 8.1%
99
99
99
99
99
99
99
99
100
100
Module 1.7%
98
98
99
99
99
100
99
100
100
98
Nomodule 0.2%
96
100
100
← few of this category on the pagemany →
60%95%+ of sites passing INP Faded cells: under 100 sites

Each row is a category, each column its own count bucket (few on the left, many on the right); the cell is the share of those sites passing INP.

No category moves the INP pass rate much, however many a site ships. computed

The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
4

Few vs many - does quantity cost INP? the pass rate with few vs many of each category

60%70%80%90%100% few → many
Inline 40.6% 99% → 98%
Async 21.1% 99% → 98%
Defer 8.6% 99% → 99%
Module 1.7% 98% → 98%
Other 19.8% 99% → 100%
Blocking 8.1% 99% → 100%
Nomodule 0.2% 96% → 100%
% of sites passing INP · hollow ring = pages with few, solid dot = pages with many

Per category: the pass rate among pages with FEW of it (hollow ring) against pages with MANY (solid dot), worst trend first. Thin buckets are excluded from the endpoints.

More Inline costs the most: the INP pass rate falls from 99% with few to 98% with many. computed

The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
5

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

A parser-blocking script stops HTML parsing until it downloads and runs. The page freezes mid-construction. defer downloads in parallel and runs after parsing, in order. async runs the moment it lands, which is fine for independent scripts and a race condition for everything else. Modules defer by default.

Blocking scripts in the head are almost never a decision someone made this year. They are habits from before defer existed, copied from theme to theme. The mix on this page is an audit of those habits.

Go fix it async vs defer → 14 methods to defer JavaScript → Head vs footer JavaScript →
Related signals Cookies per site → Uses @import → DOM size → Images per page → Chrome field data from 94,910 sites, representing millions of real page loads · How we measured