Cost per Action (CPA), also known as Pay per Action (PPA), is an Internet advertising pricing structure, where the advertiser only pays for each specified action, whether it is submitting a form, making a purchase, downloading, etc. linked to the advertisement.
Generally direct response advertisers consider this advertising venue as they only pay once the desired action has occurred. This desired action is determined by the advertiser.
Some people often refer to CPA as Cost per Acquisition. This is not incorrect as in the majority of instances the advertiser may require the acquisition of a product or service before paying for the advertisement.
Effective cost per action
Effective cost per action (eCPA) is used to measure the effectiveness of advertising inventory purchased by the advertiser on a CPI, CPT or CPC basis. This will indicate to the advertiser what they would have paid if they purchased the advertising inventory on a CPA basis.
