How the CPA Calculator works
Cost per acquisition (cost per order) is the most direct advertising number: how much advertising you bought for each order. Compare it with the profit that order earns before ads and you know instantly if the campaign makes money.
CPA rises when either clicks get more expensive or fewer clicks convert. Enter clicks too and the calculator shows the conversion rate so you can tell which one moved.
Formula
- CPA = Ad spend ÷ Orders
- Profit after ads = Profit per order before ads − CPA
- Conversion rate = Orders ÷ Clicks × 100
Example
$12.50 per order against $11.50 pre-ad profit: each sponsored order loses $1.
Ad spend: 600Orders from ads: 48Clicks (optional): 500Profit per order before ads (optional): 11.5
Frequently asked questions
CPA vs ACoS?
ACoS relates spend to sales value; CPA relates it to order count. CPA is easier to compare with profit per unit.
What is a good CPA?
Below your profit per order before ads, ideally under 60% of it so that returns and price changes do not push you into a loss.