Cost per acquisition (CPA) is a marketing metric that measures the total cost of acquiring a new customer. It includes all expenses related to marketing and sales efforts, such as advertising costs, promotions, and sales team salaries, divided by the number of new customers gained during a specific period. This helps businesses understand how much they are spending to attract each customer. By analyzing CPA, companies can evaluate the effectiveness of their marketing strategies and make informed decisions about budget allocation. A lower CPA indicates a more efficient marketing campaign, while a higher CPA may signal the need for adjustments to improve customer acquisition efforts.