Definition
CPM is the cost of showing an ad one thousand times. It reflects how competitive and expensive it is to reach your audience.
CPM explained
CPM is driven by auction competition, audience size, season, placement and how engaging your ad is. A rising CPM can signal holiday competition or audience saturation. CPM should always be read alongside click-through rate and cost per result.
Formula
CPM = (spend ÷ impressions) × 1,000
Example
Spending 300 dollars for 25,000 impressions gives a CPM of 12 dollars.
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