Paid Search

CPM (Cost Per Mille)

CPM is the cost an advertiser pays per one thousand ad impressions, common in awareness and display campaigns.

It suits goals built around visibility rather than direct clicks or conversions. For example, a brand campaign might optimise for low CPM to maximise reach. It measures exposure cost, not response, so pair it with engagement metrics.

CPM buys exposure, so its evaluation belongs with exposure goals: cost to reach the intended audience, not cost per click that the format was never optimising for. Comparing CPMs is only meaningful with targeting held constant, a low CPM on a broad audience is usually just cheaper people, not better buying. The metric pairs with frequency and reach to answer the real question: what did it cost to put the message in front of how many of the right people, how many times. Awareness campaigns judged on clicks get cancelled precisely when they are working.