Site speed is one of the few things that hurts you twice: slow stores rank worse and convert worse. Google’s Core Web Vitals put numbers on it — and for ecommerce, those numbers are money.

What Core Web Vitals measure

  • LCP (Largest Contentful Paint) — how quickly the main content loads. Aim for under 2.5s.
  • INP (Interaction to Next Paint) — how responsive the page feels when tapped or clicked.
  • CLS (Cumulative Layout Shift) — how much the layout jumps around as it loads.

Why it’s a commercial issue

Every extra second of load time measurably reduces conversion. On mobile — where most ecommerce traffic lives — the effect is even sharper. A store that loads in 1.8s will out-earn the same store at 4s, on the same traffic.

Common culprits

  • Too many apps and third-party scripts
  • Huge, unoptimised images
  • Heavy themes and render-blocking code
  • Legacy platforms that are slow by design

How to fix it

Optimise and lazy-load images, cut unnecessary apps and scripts, and use a lean, well-built theme. If your platform is the bottleneck, moving to Shopify is often the cleanest fix — it’s fast by default.

Want to know what’s slowing you down? Book a performance audit and we’ll show you exactly where the seconds — and sales — are going.