Shopify cacheable resource share and the Core Web Vitals

Sites with 80%+ cacheable resources cacheable resource share have a good LCP most often: 97%, against 96% of all Shopify sites. Sites with 50% to 79% cacheable resources cacheable share have it least often, at 94%.

80%+ cacheable resources is the most used: 60.7% of Shopify sites.

Across the four LCP sub-parts in Chrome's field data, the largest gap between 80%+ cacheable resources and 50% to 79% cacheable resources sits in element render delay: 265 ms median for 80%+ cacheable resources against 359 ms for 50% to 79% cacheable resources. Overall median field LCP is 1.2s for 80%+ cacheable resources (TTFB 381 ms, load delay 558 ms, load duration 220 ms, render delay 265 ms) versus 1.5s for 50% to 79% cacheable resources.

jQuery sets the cacheable resource share to 80%+ cacheable resources on 54% of its sites, and 94% of jQuery sites have a good LCP, against 96% of all sites.

FrameworkCacheable resource share on its sitesGood LCP

All Shopify sites 8,246 sites80%+ cacheable resources 61%50% to 79% cacheable resources 39%96%

Vue 933 sites80%+ cacheable resources 53%50% to 79% cacheable resources 47%95%

jQuery 3,153 sites80%+ cacheable resources 54%50% to 79% cacheable resources 45%94%

80%+ cacheable resources 50% to 79% cacheable resources 20% to 49% cacheable resources Under 20% cacheable resources

Does the framework explain the cacheable resource share difference?

On jQuery, 96% of sites with 80%+ cacheable resources cacheable resource share have a good LCP, against 91% of jQuery sites with 50% to 79% cacheable resources. Within jQuery, sites with 80%+ cacheable resources have a good LCP more often. On Vue, 96% of sites with 80%+ cacheable resources cacheable resource share have a good LCP, against 94% of Vue sites with 50% to 79% cacheable resources. Within Vue, sites with 80%+ cacheable resources and 50% to 79% cacheable resources have a good LCP about equally often.

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 5,006 sites (60.7%) with 80%+ cacheable resources and 3,214 sites (39.0%) at 50% to 79%, 97% and 94% pass field LCP (1.2s and 1.5s median). When cacheability falls to 20% to 49% (0.3%), good LCP drops to 80% (1.3s median), and below 20% cacheable (<0.1%, 1 sites) good LCP drops to 100% (1.4s median).