Why are modeled conversions sometimes fractional?

A conversion rate is an average. Multiplying clicks by that rate gives an expected count, which need not be a whole observed event.

Should revenue per conversion include lifetime value?

Only if the same, supportable lifetime-value definition is used consistently. For a conservative snapshot, use recognized revenue in the selected attribution period.

Does the result include agency fees or overhead?

No. Add those costs outside this model or include conversion-linked portions in variable cost per conversion.

Can the calculator predict future CPC?

No. Average CPC is an input. Auction prices and campaign performance can change.

CPC ROI and Paid Campaign Profit Calculator

Connect click cost to conversion economics without treating ROAS as profit.

ROI and ROAS side by side

Variable costs included

Transparent scenario assumptions

CurrencyPaid clicksWhole number of clicks in the modeled campaign.Average cost per clickUse actual average CPC or a planning estimate, not a maximum bid.Conversion rate (%)Revenue per conversionVariable cost per conversionInclude fulfillment, payment, or other costs that occur per conversion.

How to Model CPC Campaign ROI

Keep every monetary input in one currency and use data from the same attribution window.

Enter the number of paid clicks and average cost per click.

Use contribution economics

Variable cost per conversion prevents gross revenue from being mistaken for profit. Add fixed overhead separately when evaluating the wider business.

What the CPC ROI Result Means

The model purchases the entered clicks at the entered average CPC. Fractional modeled conversions are allowed because conversion rate is an expected average. ROI uses ad spend plus conversion-linked variable costs as the denominator; ROAS uses ad spend alone. A negative ROI means modeled revenue does not recover those included costs.

Paid Campaign ROI Examples

Positive contribution campaign

Traffic and unit economics

clicks:1000

averageCpc:2

conversionRate:5

revenuePerConversion:100

variableCostPerConversion:20

Modeled ROI

66.67% ROI

Ad spend is 2,000; 50 modeled conversions produce 5,000 revenue and 1,000 variable costs. Profit is 2,000 on 3,000 total modeled investment.

Traffic with no conversions

Traffic and unit economics

clicks:100

averageCpc:1.25

conversionRate:0

revenuePerConversion:80

variableCostPerConversion:10

Modeled ROI

-100% ROI

The 125 ad spend produces no modeled revenue, so the included investment is fully unrecovered.

Compare like with like

Use one attribution window and one revenue definition across the clicks, conversions, and monetary inputs.

Frequently Asked Questions

No. ROAS divides revenue by ad spend. This ROI subtracts both ad spend and entered variable costs, then divides profit by those included costs.

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CPC ROI, Profit, and ROAS Formulas

Google Ads defines average CPC as total click cost divided by clicks. This model uses that observed or assumed unit cost to build a separate profitability scenario.

Formula

ad spend = clicks × average CPC; conversions = clicks × conversion rate ÷ 100

Ad spend and conversions

ad spend = clicks × average CPC; conversions = clicks × conversion rate ÷ 100

Campaign ROI

ROI = (revenue − ad spend − variable costs) ÷ (ad spend + variable costs) × 100

ROAS

ROAS = revenue ÷ ad spend

Scientific Background

The arithmetic is deterministic and uses no benchmark conversion rate, click price, attribution model, or lifetime-value assumption.