The State of Web Vitals

Shopify HTTP ETag cache validators and the Core Web Vitals

99.9% of audited sites (8,239) serve ETag headers on their responses (95% good LCP, 1.4s median), while 0.1% omit ETag validators (100% good LCP, 1.2s median).

Field data PhoneDesktopAll Scope All sites October 2026 edition · Phone field outcomes · Shopify sites only
Shopify Scoped to 8,248 sites out of 203,892 analyzed (cms) Compare with all sites →

0.1% of Shopify sites have no ETag cache validation. Of the 99.9% that do, 100% use ETag validators, 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
1

LCP pass rate

Sites with ETag validators ETag cache validation have a good LCP most often: 95%, against 95% of all Shopify sites.

SitesGood, needs improvement, poor LCPMedian
All Shopify sites5,82595%1.4s
No ETag header 0.1%5100%1.2s
ETag header present 99.9%5,82095%1.4s
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

ETag cache validation usage

99.9% of Shopify sites use ETag cache validation, and 100% of those use ETag validators.

All Shopify sites 8,246 sites
ETag cache validation 99.9%
Sites with ETag cache validation 8,239 sites
ETag header present 100.0%
ETag header 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 ETag headers

Across the four LCP sub-parts in Chrome's field data, the largest gap between ETag validators and no ETag header sits in time to first byte (TTFB): 402 ms median for ETag validators against 277 ms for no ETag header. Overall median field LCP is 1.4s for ETag validators (TTFB 402 ms, load delay 590 ms, load duration 206 ms, render delay 312 ms) versus 1.2s for no ETag header.

Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
All Shopify sites 5,048402 ms590 ms206 ms312 ms590 mslab 596 ms1.4s
ETag header present 5,043402 ms590 ms206 ms312 ms590 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

ETag cache validation per framework

Vue sets the ETag cache validation to ETag validators on 100% of its sites, and 94% of Vue sites have a good LCP, against 95% of all sites.

FrameworkETag cache validation on its sitesGood LCP
All Shopify sites 8,246 sitesETag header present 100%95%
Vue 933 sitesETag header present 100%94%
jQuery 3,153 sitesETag header present 100%93%
ETag header present No ETag header
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
5

ETag headers or the framework

Why ETag headers matter on repeat visits and CDN edge revalidations

An Entity Tag (ETag) is an opaque version identifier attached to an HTTP response. Across 8,239 audited sites (99.9%) that emit ETag headers, browsers and CDN edges can send If-None-Match conditional requests when cached files expire and receive a header-only 304 Not Modified response instead of re-downloading the full payload. Because first-visit crawl and field LCP measurements weight initial loads and immutable hashed assets heavily, sites with ETag headers record 95% good LCP (1.4s median, 402 ms TTFB) while the 0.1% without ETag headers record 100% good LCP (1.2s median, 277 ms TTFB).

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
6

Understanding HTTP ETag cache validators

Enable strong or weak content-based ETag headers on your web server or CDN edge so expired cache entries can revalidate via If-None-Match and 304 Not Modified in a single header-only round trip. If you run multiple origin servers behind a load balancer, avoid inode-based default ETags in Apache or nginx so revalidation requests never miss across nodes. Across all audited sites, 99.9% emit ETag validators (95% good LCP, 1.4s median) and 0.1% omit them (100% good LCP, 1.2s median).

Go fix it TTFB: cache duration →
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 Last-Modified present → Uncompressed text responses → Main CDN → HTTP protocol → By Arjen Karel · 8,246 crawled Shopify sites (5,825 with phone Chrome field data, October 2026) · How we measured