Website ROI Calculator

We take the extra conversions a higher conversion rate produces on your existing traffic — visitors × current conversion rate × the relative uplift — value them at your order value and gross margin, then compare that monthly gain to the one-off project cost plus ongoing upkeep. ROI is the 12-month net gain divided by total cost. The full formula is shown under “How is this calculated?”.

It depends on how much traffic you already have and how much the redesign lifts conversion — a small uplift on high traffic can pay back fast, while a costly rebuild on low traffic may not. Rather than chase a single benchmark, set the uplift conservatively and look at the payback period: a redesign that recoups its cost well within a year is the healthy direction.

Payback is the first month your cumulative net gain — after the one-off project cost — turns positive. This calculator applies the conversion uplift from month one; if your new site rolls out in stages or takes time to settle, lower the uplift or the traffic to stress-test the payback.

The pre-filled numbers are demonstration defaults that produce a realistic example — they are not claimed industry averages. Replace them with your own figures for an accurate result. Where a field is labelled as an assumption, adjust it to match your business; the methodology page lists every default and its status.

No. Every calculation runs entirely in your browser. Nothing you type is sent to a server — there is no account and no copy of your numbers. If you download the PDF report, only the email you enter on the report form is stored, so we can follow up; your inputs stay on your device.