How Website Speed Affects Your Sales (And How to Improve It)

Amazon famously found that every 100ms of latency cost them 1% in sales. You're not Amazon — but the math is brutal at any size.

The real cost of a slow site

If your site loads in 5 seconds instead of 2, you're losing roughly 20% of mobile visitors before they see your hero. Multiply that by your traffic and average deal size — that's the leak.

What Google actually measures

• LCP (Largest Contentful Paint) — how fast the biggest above-fold element appears. Target under 2.5s.
• INP (Interaction to Next Paint) — how snappy buttons feel. Target under 200ms.
• CLS (Cumulative Layout Shift) — how much the page jumps. Target under 0.1.

Images: the #1 fix

Convert to WebP/AVIF, serve responsive sizes via srcset, lazy-load anything below the fold, and never ship a 4000px image to a 400px container.

Fonts that don't block render

Self-host or use font-display: swap. Preload your one critical font weight. Skip the 6 weights you'll never use.

Trim the JavaScript

Audit third-party scripts (chat widgets, analytics, tag managers) — each one costs 50–300ms. Defer non-critical JS and code-split routes.

Hosting & CDN done right

Cheap shared hosting will cap your performance no matter what you optimize. Use edge hosting (Cloudflare, Vercel) so static assets load from the user's nearest city.

Your 30-minute speed checklist

1. Run PageSpeed Insights — note LCP and CLS.
2. Compress hero image to WebP, under 150KB.
3. Remove unused fonts and weights.
4. Add loading="lazy" to below-fold images.
5. Audit third-party scripts — kill the ones with no clear ROI.