Shopify unused JavaScript bytes and the Core Web Vitals

Sites with 850 KB to 1.5 MB of unused JS unused JavaScript bytes have a good INP most often: 99%, against 93% of all Shopify sites. Sites with over 1.5 MB of unused JS unused JS have it least often, at 91%.

Sites with 400 to 850 KB of unused JS unused JavaScript bytes have a good LCP most often: 99%, against 95% of all Shopify sites. Sites with over 1.5 MB of unused JS unused JS have it least often, at 94%.

Over 1.5 MB of unused JS is the most used: 64.0% of Shopify sites. 850 KB to 1.5 MB of unused JS is 23.2% of Shopify sites.

On jQuery, 74% of sites use over 1.5 MB of unused JS unused JavaScript bytes, and 92% of jQuery sites have a good INP, against 93% of all sites. On Vue, 83% of sites use over 1.5 MB of unused JS, and 91% of Vue sites have a good INP.

On jQuery, 74% of sites use over 1.5 MB of unused JS unused JavaScript bytes, and 93% of jQuery sites have a good LCP, against 95% of all sites. On Vue, 83% of sites use over 1.5 MB of unused JS, and 94% of Vue sites have a good LCP.

FrameworkUnused JavaScript bytes on its sitesGood INP

Shopify sites with unused JavaScript bytes 8,245 sitesOver 1.5 MB unused 64%850 KB to 1.5 MB unused 23%400 to 850 KB unused 13%93%

jQuery 3,152 sitesOver 1.5 MB unused 74%850 KB to 1.5 MB unused 20%92%

Vue 933 sitesOver 1.5 MB unused 83%850 KB to 1.5 MB unused 15%91%

Over 1.5 MB unused 850 KB to 1.5 MB unused 400 to 850 KB unused Under 400 KB unused

Does the framework explain the unused JavaScript bytes difference?

On jQuery, 100% of sites with 850 KB to 1.5 MB of unused JS unused JavaScript bytes have a good INP, against 91% of jQuery sites with over 1.5 MB of unused JS. Within jQuery, sites with 850 KB to 1.5 MB of unused JS have a good INP more often. On Vue, 97% of sites with 850 KB to 1.5 MB of unused JS unused JavaScript bytes have a good INP, against 90% of Vue sites with over 1.5 MB of unused JS. Within Vue, sites with 850 KB to 1.5 MB of unused JS and over 1.5 MB of unused JS have a good INP about equally often.

On jQuery, 97% of sites with 400 to 850 KB of unused JS unused JavaScript bytes have a good LCP, against 92% of jQuery sites with over 1.5 MB of unused JS. Within jQuery, sites with 400 to 850 KB of unused JS and over 1.5 MB of unused JS have a good LCP about equally often. On Vue, 94% of sites with over 1.5 MB of unused JS unused JavaScript bytes have a good LCP, against 97% of Vue sites with 850 KB to 1.5 MB of unused JS. Within Vue, sites with over 1.5 MB of unused JS and 850 KB to 1.5 MB of unused JS have a good LCP about equally often.

How dead JavaScript code still blocks the main thread

The browser cannot skip parsing or compiling unused functions inside a downloaded bundle. Across 1,047 sites (12.7%) with 400 to 850 KB of unused JS, 98% pass field INP at an 85ms median, while the 64.0% (5,280) exceeding 1.5 MB of unused JS drop to 91% good INP (121ms median).