Cacheable resource share and the Core Web Vitals
33.6% of audited sites (69,271) mark 80% or more of their subresources as cacheable and reach 84% good LCP (1.5s median), compared to 79% good LCP (1.6s median) on the 31.0% caching under 20% of resources.
24.0% of sites use 50% to 79% cacheable resources cacheable resource share, and 85% of those sites have a good LCP, against 82% of all sites.
LCP pass rate
Sites with 50% to 79% cacheable resources cacheable resource share have a good LCP most often: 85%, against 82% of all sites. Sites with under 20% cacheable resources cacheable share have it least often, at 79%.
Cacheable resource share usage
80%+ cacheable resources is the most used: 33.6% of sites. 50% to 79% cacheable resources is 24.0% of sites.
LCP phase breakdown by share of cacheable subresources
Across the four LCP sub-parts in Chrome's field data, the largest gap between 50% to 79% cacheable resources and under 20% cacheable resources sits in time to first byte (TTFB): 578 ms median for 50% to 79% cacheable resources against 760 ms for under 20% cacheable resources. Overall median field LCP is 1.5s for 50% to 79% cacheable resources (TTFB 578 ms, load delay 343 ms, load duration 138 ms, render delay 238 ms) versus 1.6s for under 20% cacheable resources.
Understanding cacheable resource share
How subresource Cache-Control coverage speeds up repeat visits and CDN edge hits
Cacheable resource share tracks the percentage of page requests carrying valid Cache-Control or Expires headers. Across 69,271 sites (33.6%) with 80%+ cacheable resources and 49,403 sites (24.0%) at 50% to 79%, 84% and 85% pass field LCP (1.5s and 1.5s median). When cacheability falls to 20% to 49% (11.5%), good LCP drops to 82% (1.5s median), and below 20% cacheable (31.0%, 63,848 sites) good LCP drops to 79% (1.6s median).
Ensure at least 80% of subresources return explicit Cache-Control max-age headers so browsers and CDN edges serve static assets without origin round-trips. Across all audited sites, 33.6% cache 80%+ of resources (84% good LCP) versus 31.0% caching under 20% (79% good LCP).
How cacheable resource share plays out per platform
What the field data shows when you isolate a single CMS or framework.
35.9% of WordPress sites mark under 20% of resources cacheable (66% good LCP vs 72% at 80%+).
Across 65,509 WordPress sites, 38.8% mark 80%+ of subresources as cacheable (72% good LCP), 17.3% cache 50% to 79% (75% good LCP), and 35.9% cache under 20% (66% good LCP).
100% of Shopify stores cache at least 50% of subresources (97% good LCP at 80%+ cacheable).
Across Shopify storefronts, 61.3% mark 80%+ of resources as cacheable (97% good LCP) and 38.4% cache 50% to 79% (94% good LCP).
React & Next.js sites caching under 20% of resources (9.5%) pass LCP at 62% vs 88% at 80%+ (26 points apart).
Across React sites, 58.3% cache 80%+ of assets (88% good LCP), 28.8% cache 50% to 79% (88%), and 9.5% cache under 20% (62% good LCP).
By Arjen Karel · 210,902 crawled sites (196,263 with all devices Chrome field data, 206,258 sites with cacheable resource share, October 2026). How we measured.