Shopify HTTP Last-Modified headers and the Core Web Vitals
Whether responses carry Last-Modified validators.
100.0% of Shopify sites use Last-Modified headers Last-Modified cache validation, and 95% of those sites have a good LCP, against 95% of all Shopify sites.
The State of Web Vitals · October 2026 · Shopify: 8,246 crawled sites · 5,825 with phone field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
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LCP pass rate
Sites with Last-Modified headers Last-Modified cache validation have a good LCP most often: 95%, against 95% of all Shopify sites.
SitesGood, needs improvement, poor LCPMedian
All Shopify sites5,8251.4s
Last-Modified present 100.0%5,8251.4s
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · Shopify: 8,246 crawled sites · 5,825 with phone field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
2
Last-Modified cache validation usage
Last-Modified headers is the most used: 100.0% of Shopify sites.
Last-Modified present 100.0%
Last-Modified present 100.0%
The State of Web Vitals · October 2026 · Shopify: 8,246 crawled sites · 5,825 with phone field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
3
LCP phase breakdown for sites with and without Last-Modified headers
Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
All Shopify sites 5,048590 mslab 596 ms1.4s
Last-Modified present 5,048590 mslab 596 ms1.4s
TTFB Resource load delay Resource load time Element render delay
The State of Web Vitals · October 2026 · Shopify: 8,246 crawled sites · 5,825 with phone field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
4
Last-Modified cache validation per framework
jQuery sets the Last-Modified cache validation to Last-Modified headers on 100% of its sites, and 93% of jQuery sites have a good LCP, against 95% of all sites.
FrameworkLast-Modified cache validation on its sitesGood LCP
All Shopify sites 8,246 sitesLast-Modified present 100%95%
Vue 933 sitesLast-Modified present 100%94%
jQuery 3,153 sitesLast-Modified present 100%93% Last-Modified present
The State of Web Vitals · October 2026 · Shopify: 8,246 crawled sites · 5,825 with phone field dataBy Arjen Karel · corewebvitals.io/state-of-cwv
Related signals HTTP protocol → HTML size (kB) → Connection hints → HTML compression → By Arjen Karel · 8,246 crawled Shopify sites (5,825 with phone Chrome field data, October 2026) · How we measured
By Arjen Karel · 8,246 crawled Shopify sites (5,825 with phone Chrome field data, October 2026). How we measured.