Cost per acquisition answers a blunt question: what did it cost to get one customer? Add up all the spending on a campaign, divide by the number of conversions. If you spent ten thousand dollars and gained two hundred customers, your CPA is fifty dollars.

The number only matters next to customer value. A fifty-dollar CPA is excellent if each customer spends five hundred. It is a disaster if they spend sixty and never return.

What belongs in the calculation

• Media spend
• Creative production
• Platform and tool fees
• Agency or freelancer costs

Many teams track CPA by channel to see where efficiency lives. The trap is over-optimizing for cheap conversions and ignoring customers who churn fast. Cheap acquisition of the wrong people is still waste.