Cost per acquisition (CPA) is a metric that measures the cost to acquire a paying customer. It's similar to cost per conversion (CVR) and cost per lead (CPL) but usually used to measure the performance of a single advertising channel or campaign. It's calculated by dividing the total campaign spend by the number of conversions. For example, if you generated 100 purchases through Google Ads that cost $1000, the CPA would be $10.

Cost per acquisition lets you directly determine the effectiveness of your marketing campaigns. CPA is a good metric to track but can be misleading when tracked alone, it's best when calculated along ROI, ROAS, AOV, and CVR.