Cost Per Mille (CPM)

Cost per mille (CPM) is the price an advertiser pays for every 1,000 ad impressions delivered (‘mille’ is Latin for ‘thousand’). It is calculated as the total cost of an online ad campaign divided by the number of impressions multiplied by 1,000. For example, if a publisher charges €2,000 for an ad on its website and the ad delivers 200,000 impressions, the CPM is €10 (2,000 ÷ 200,000 × 1,000) – so the advertiser is paying €10 for every 1,000 impressions.