Glossary/Measurement & Attribution/Cost Per Acquisition (CPA)
Measurement & Attribution
Cost Per Acquisition (CPA)
The cost to drive one conversion, such as a sale or signup.
By Brandon Mina·CEO, BrandPilot AI·Updated November 2026
Short answer
Cost per acquisition (CPA) is the average cost to drive one conversion, such as a sale, signup or lead. It is calculated by dividing total campaign spend by the number of conversions. CPA shows acquisition efficiency and is often a bidding target in ad platforms, ideally compared against customer lifetime value or contribution margin.