Shopify CLS shift concentration and the Core Web Vitals
Among sites recording lab layout shifts, 57.5% (3,099) concentrate 95% or more of their CLS into a single shift (94% good field CLS), while 18.8% suffer multiple compounding shifts (90% good field CLS).
57.5% of Shopify sites use a single dominant shift CLS shift concentration, and 94% of those sites have a good CLS, against 94% of all Shopify sites.
CLS pass rate
Sites with a single dominant shift CLS shift concentration have a good CLS most often: 94%, against 94% of all Shopify sites. Sites with mostly one shift shift concentration have it least often, at 90%.
CLS shift concentration usage
A single dominant shift is the most used: 57.5% of Shopify sites.
CLS shift concentration per framework
Vue sets the CLS shift concentration to a single dominant shift on 55% of its sites, and 90% of Vue sites have a good CLS, against 94% of all sites.
jQuery 2,327 sitesSingle dominant shift (95%+) 53%Mostly one shift (65-94%) 25%Multiple compounding shifts (<65%) 22%91%
Vue 669 sitesSingle dominant shift (95%+) 55%Mostly one shift (65-94%) 24%Multiple compounding shifts (<65%) 21%90%CLS shift concentration or the framework
Does the framework explain the CLS shift concentration difference?
On jQuery, 91% of sites with a single dominant shift CLS shift concentration have a good CLS, against 85% of jQuery sites with mostly one shift. Within jQuery, sites with a single dominant shift have a good CLS more often. On Vue, 88% of sites with a single dominant shift CLS shift concentration have a good CLS, against 87% of Vue sites with mostly one shift. Within Vue, sites with a single dominant shift and mostly one shift 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 3,099 sites (57.5%) where one isolated element accounts for at least 95% of total CLS, 94% pass field CLS. When secondary shifts join in (23.7% at 65% to 94% concentration), good field CLS drops to 90%, and when shifts are spread across multiple compounding events (18.8%, 1,011 sites), good field CLS falls to 90%.
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, 57.5% have a single dominant shift (94% good CLS) and 18.8% have multiple compounding shifts (90% good CLS).
By Arjen Karel · 8,246 crawled Shopify sites (5,825 with phone Chrome field data, 5,389 sites with CLS shift concentration, October 2026). How we measured.