What is the difference between CPM and RPM?

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CPM (Cost Per Mille) and RPM (Revenue Per Mille) are two commonly used terms in online advertising.

CPM refers to the amount an advertiser pays for every 1,000 impressions of their ad. It is a cost-based metric and is used to calculate the cost of running an ad campaign. For example, if an advertiser pays $5 CPM, they will pay $5 for every 1,000 times their ad is displayed.

RPM, on the other hand, is a revenue-based metric that measures the earnings generated per 1,000 impressions. RPM is calculated by dividing the estimated earnings by the number of pageviews, then multiplying by 1,000. For example, if a website earns $10 from 2,000 pageviews, the RPM would be $5 ($10 / 2,000 x 1,000).

In short, CPM is a cost metric that measures how much an advertiser pays for every 1,000 impressions, while RPM is a revenue metric that measures how much a publisher earns for every 1,000 impressions.