A Cost Per Action (CPA) is when there is only a cost when someone performs the desired action.
This is quite similar to CPC.
An example of CPA is when you have an advert encouraging people to buy your products. A customer buying your product would be an action therefore unless that happens, and you use a CPA your company would not have to pay.
Let’s say you had an ad under CPA and it was 5 per Action. Your ad was seen by 2000 people, 100 people clicked on the link to your website and 10 people brought an item. This would mean you would only cost 50 because only 10 people did the desired action of the ad.
CPA is a performance indicator that is used in business reports to show how well a business is doing.