How does website speed affect revenue?

Widely cited research shows conversion rates drop roughly 4–7% for every additional second of load time beyond about two seconds. On meaningful traffic that compounds into significant lost revenue.

Is this estimate accurate for my business?

It is an indicative model based on industry averages. Your real figures depend on sector, audience and overall UX — use it to size the opportunity, then validate with analytics.

How do I find my load time?

Run our free Website Grader, which reports mobile and desktop performance using Google PageSpeed Insights.

Free · Website ROI

What Is Your Slow Website Costing You?

A slow or dated site quietly leaks revenue every day. Estimate how much a faster, better-converting website could be worth to you.

Your numbers

Monthly website visitors

Current conversion rate (%)

Average order / lead value (£)

Current page load time (seconds)

Not sure of your load time? Run our free Website Grader first.

Estimated impact

Enter your visitors and order value to see the estimate.

Stop leaking revenue to a slow website

JW Digital builds fast, conversion-focused websites on a high-performance Next.js stack — and redesigns underperforming sites without losing your rankings.

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