Free calculator
CPA calculator
Cost per acquisition: how much one acquired customer or conversion from a campaign costs on average.
Cost per acquisition (CPA)
A conversion can be a purchase, an enquiry or a registration, depending on what the campaign collects.
- CPA
- — Kč
What CPA is and how it's calculated
CPA (Cost per Acquisition) is the average cost of one acquired customer or conversion:
CPA = campaign costs / number of conversions
A campaign for 12,000 Kč that brought 40 orders has a CPA of 12,000 / 40 = 300 Kč. That's what it cost on average to bring one customer to a purchase.
What CPA is acceptable
The number alone says nothing. It gains meaning in comparison with how much the customer brings. An acquisition for 300 Kč is great on an order with a gross profit of 800 Kč and disastrous on a product where a hundred remains. For repeat purchases, CPA is measured against customer lifetime value (CLV): the first purchase may even be loss-making if the customer keeps coming back. The first contact is always the most expensive.
What to watch out for
- Count conversions, not clicks. CPA with clicks in the numerator is CPC, a different metric with a different use.
- Campaign management belongs in the costs too, just as with PNO; CPA based only on ad credit looks better than reality.
- Track CPA by channel. An average across all campaigns masks the channel that's simply making acquisition more expensive.
Where to go next
You can do the maths. But what next? How to turn customers who bought once into customers who buy repeatedly is the subject of the book Opakovaný prodej.