The State of Web Vitals

CLS shift concentration on Wix sites

Among sites recording lab layout shifts, 72.9% (746) concentrate 95% or more of their CLS into a single shift (97% good field CLS), while 14.5% suffer multiple compounding shifts (95% good field CLS).

Field data PhoneDesktopAll Scope All sites October 2026 edition · Phone field outcomes · Wix sites only
Wix Scoped to 5,623 sites out of 203,892 analyzed (cms) Compare with all sites →

72.9% of Wix sites use a single dominant shift CLS shift concentration, and 97% of those sites have a good CLS, against 97% of all Wix sites.

The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 3,077 with phone field data · 1,024 sites with CLS shift concentrationBy Arjen Karel · corewebvitals.io/state-of-cwv
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CLS pass rate

Sites with a single dominant shift CLS shift concentration have a good CLS most often: 97%, against 97% of all Wix sites.

SitesGood, needs improvement, poor CLSMedian
All Wix sites3,07797%0.00
Single dominant shift (95%+) 72.9%39597%0.00
Multiple compounding shifts (<65%) 14.5%8395%0.00
Mostly one shift (65-94%) 12.7%8289%0.00
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 3,077 with phone field data · 1,024 sites with CLS shift concentrationBy Arjen Karel · corewebvitals.io/state-of-cwv
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CLS shift concentration usage

A single dominant shift is the most used: 72.9% of Wix sites.

Single dominant shift (95%+) 72.9% Multiple compounding shifts (<65%) 14.5% Mostly one shift (65-94%) 12.7%
Single dominant shift (95%+) 72.9% Multiple compounding shifts (<65%) 14.5% Mostly one shift (65-94%) 12.7%
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 3,077 with phone field data · 1,024 sites with CLS shift concentrationBy Arjen Karel · corewebvitals.io/state-of-cwv
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CLS shift concentration per framework

React sets the CLS shift concentration to a single dominant shift on 73% of its sites, and 97% of React sites have a good CLS, against 97% of all sites.

FrameworkCLS shift concentration on its sitesGood CLS
Wix sites with CLS shift concentration 1,024 sitesSingle dominant shift (95%+) 73%Multiple compounding shifts (<65%) 14%Mostly one shift (65-94%) 13%97%
React 1,023 sitesSingle dominant shift (95%+) 73%Multiple compounding shifts (<65%) 14%Mostly one shift (65-94%) 13%97%
Single dominant shift (95%+) Multiple compounding shifts (<65%) Mostly one shift (65-94%)
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 3,077 with phone field data · 1,024 sites with CLS shift concentrationBy Arjen Karel · corewebvitals.io/state-of-cwv
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CLS shift concentration or the framework

Does the framework explain the CLS shift concentration difference?

On React, 97% of sites with a single dominant shift CLS shift concentration have a good CLS, against 95% of React sites with multiple compounding shifts. Within React, sites with a single dominant shift and multiple compounding shifts have a good CLS about equally often.

One isolated layout jump versus cascading multi-element shifts

CLS concentration measures the ratio of the single largest layout shift to total lab CLS on pages with non-zero shift. Across 746 sites (72.9%) where one isolated element accounts for at least 95% of total CLS, 97% pass field CLS. When secondary shifts join in (12.7% at 65% to 94% concentration), good field CLS drops to 89%, and when shifts are spread across multiple compounding events (14.5%, 148 sites), good field CLS falls to 95%.

The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 3,077 with phone field data · 1,024 sites with CLS shift concentrationBy Arjen Karel · corewebvitals.io/state-of-cwv
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Understanding CLS shift concentration

Inspect every LayoutShift entry in your performance trace: if concentration is 95%+, fixing the single culprit container resolves CLS; if concentration is below 65%, audit header bars, web fonts, and unsized media together. Across all audited sites with lab shifts, 72.9% have a single dominant shift (97% good CLS) and 14.5% have multiple compounding shifts (95% good CLS).

Go fix it Scroll-triggered animations cause CLS → Layout shift caused by CSS transitions → Identify and fix CLS →
The State of Web Vitals · October 2026 · Wix: 5,621 crawled sites · 3,077 with phone field data · 1,024 sites with CLS shift concentrationBy Arjen Karel · corewebvitals.io/state-of-cwv
Related signals Largest single shift → Layout shift count → Shift direction → What shifted → By Arjen Karel · 5,621 crawled Wix sites (3,077 with phone Chrome field data, 1,024 sites with CLS shift concentration, October 2026) · How we measured