Website return and payback calculator
Turn a website budget into a transparent scenario. See the difference between sales, contribution after variable costs, and the amount left after website and marketing costs.
Reproduce the example
1,000 visitors × 2% enquiry rate = 20 enquiries. At a 20% close rate that is 4 expected sales. $500 per sale gives $2,000 revenue. A 60% contribution margin leaves $1,200 after variable costs. Subtract $100 website costs and $300 marketing spend to leave $800 per month before other overhead and taxes.
With $2,000 setup, simple payback is $2,000 ÷ $800 = 2.5 months at that constant level. Over twelve months, $14,400 contribution minus $6,800 setup and running costs leaves $7,600 modeled net contribution. Return on those included costs is approximately 111.76%.
Formulas and important boundaries
Expected sales = visitors × enquiry rate × close rate. Sales revenue × contribution margin = contribution after variable costs. Monthly modeled net contribution = contribution − website costs − marketing spend. First-year net contribution subtracts twelve months of running costs and one setup payment. The displayed return divides that first-year amount by included setup and running costs.
This is not accounting profit or proof that the website caused those sales. Other overhead, taxes, cash timing, financing, repeat purchases, refunds and ramp-up periods are excluded unless you explicitly incorporate them in your assumptions. Do not count marketing spend again inside the margin. Fractional expected sales are retained in the calculation; they are averages, not partial actual customers.
Check a downside case
If visitors fall to 200 with the other inputs unchanged, expected sales become 0.8, contribution becomes $240, and monthly modeled net contribution becomes −$160. Positive payback is not reached. The tool reports the loss instead of replacing it with zero.
Does this predict what a new website will earn?
No. Traffic, conversion and margin are assumptions you supply. Use measured data where available and compare several scenarios.
What if my included costs are zero?
A percentage return with a zero cost denominator is undefined. With no setup cost there is nothing to recover, but monthly operating losses can still occur.