Commerce Performance Index — September 2026
Evaluating Core Web Vitals pass rates, real-world Chrome field percentiles, and third-party script bloat across 58,200 active online stores.
Master Platform Comparison Table
| Platform | Sample | CWV Pass Rate | LCP p75 | INP p75 | CLS p75 | Avg 3rd-Party Scripts | Avg Script Payload |
|---|---|---|---|---|---|---|---|
| Shopify | 25,400 | 38.4% | 2,840ms | 218ms | 0.06 | 22.4 | 840 KB |
| WooCommerce | 18,200 | 34.1% | 3,150ms | 192ms | 0.08 | 14.8 | 510 KB |
| BigCommerce | 4,600 | 41.2% | 2,720ms | 204ms | 0.05 | 19.2 | 720 KB |
| Magento / Adobe | 6,800 | 24.6% | 3,680ms | 275ms | 0.12 | 28.6 | 1,140 KB |
| Shopware | 3,200 | 44.8% | 2,610ms | 185ms | 0.04 | 16.1 | 580 KB |
Analytical Insights & Observations
1. Shopify vs. Self-Hosted WooCommerce: While Shopify provides superior global TTFB due to Cloudflare Anycast edge caching, Shopify merchants install an average of 22.4 external scripts compared to 14.8 on WooCommerce. This creates higher Interaction to Next Paint (INP) friction on Shopify (218ms median vs 192ms on WooCommerce).
2. Magento Legacy Drag: Adobe Commerce / Magento storefronts recorded the lowest combined pass rate (24.6%) and highest average script weight (1,140 KB), primarily driven by legacy RequireJS bundles and un-bundled Knockout.js components.
3. Shopware Emerging Performance: Shopware 6 storefronts demonstrated the highest combined pass rate (44.8%), attributed to modern asset pipelines and disciplined default JavaScript bundling.
Data collected between August 1 and August 31, 2026. Aggregated from Google Chrome UX Report (CrUX) and Headless Chromium laboratory runs.