Short for cost per mile, CPM is a pricing model that allows advertisers to pay for ads per every 1,000 impressions. The formula for calculating CPM is:
CPM = Ad Spend ÷ Impressions × 1000
eCPM, or effective cost per mille refers to the advertising revenue publishers can get from every 1,000 impressions. eCPM is a parameter used to reflect the monetization capability of an app. The formula for calculating eCPM is:
eCPM = Total Advertising Revenue ÷ Impressions × 1000