Cacheable resource share on Wix sites

Sites with 80%+ cacheable resources cacheable resource share have a good LCP most often: 95%, against 94% of all Wix sites. Sites with 50% to 79% cacheable resources cacheable share have it least often, at 93%.

80%+ cacheable resources is the most used: 68.0% of Wix 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 time to first byte (TTFB): 400 ms median for 80%+ cacheable resources against 417 ms for 50% to 79% cacheable resources. Overall median field LCP is 1.1s for 80%+ cacheable resources (TTFB 400 ms, load delay 448 ms, load duration 113 ms, render delay 147 ms) versus 1.2s for 50% to 79% cacheable resources.

React sets the cacheable resource share to 80%+ cacheable resources on 68% of its sites, and 94% of React sites have a good LCP, against 94% of all sites.

FrameworkCacheable resource share on its sitesGood LCP

All Wix sites 5,621 sites80%+ cacheable resources 68%50% to 79% cacheable resources 32%94%

React 5,620 sites80%+ cacheable resources 68%50% to 79% cacheable resources 32%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 React, 95% of sites with 80%+ cacheable resources cacheable resource share have a good LCP, against 93% of React sites with 50% to 79% cacheable resources. Within React, 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 3,821 sites (68.0%) with 80%+ cacheable resources and 1,784 sites (31.7%) at 50% to 79%, 95% and 93% pass field LCP (1.1s and 1.2s median). When cacheability falls to 20% to 49% (0.2%), good LCP drops to 89% (1.6s median), and below 20% cacheable (0.1%, 3 sites) good LCP drops to 100% (1.4s median).