What this calculator does

Cost per conversion shows how much a campaign spends for each completed action. It is also called CPA when the conversion is an acquisition, lead or customer.

Formula used

Cost per conversion equals campaign cost divided by conversions. Conversion rate equals conversions divided by clicks, multiplied by 100. ROAS equals attributed revenue divided by campaign cost.

How to read the result

A good cost per conversion depends on margin, customer value and the quality of the conversion. A cheap lead can still be poor value if it rarely becomes a customer, while a higher CPA can work when revenue and retention are strong.

Assumptions

  • Uses campaign cost and conversions from the same reporting period.
  • Does not include agency fees unless you add them to campaign cost.
  • Attributed revenue should use the same attribution window as conversions.
  • Does not account for refunds, lifetime value, repeat purchases or offline sales unless they are included in revenue.

Sources and checks

This calculator uses a standard public formula. Where rules or thresholds can change, source links are listed on the relevant page.

Frequently asked questions

How do you calculate cost per conversion?

Divide total campaign cost by the number of conversions. For example, GBP 750 spent on 50 conversions gives a cost per conversion of GBP 15.

Is cost per conversion the same as CPA?

They are often used in the same way. CPA means cost per acquisition, so it is most precise when the conversion is a new customer, lead or signup.