RPM vs CPM
Know the difference between RPM and CPM.
RPM is the page revenue per thousand impressions, and it is calculated dividing the estimated earnings by the number of page views a publisher received, then multiplying by 1000.
CPM stands for cost per 1000 ad impressions, and it is calculated dividing the estimated earnings (publisher) or spend (advertiser) by the number of ad impressions, then multiplying by 1000.