Glossary

CPM (cost per mille)

CPM (cost per mille) is the price for one thousand ad impressions. It is the standard unit for buying display, pop, and programmatic inventory, where the advertiser pays for exposure rather than clicks or outcomes.

How to use it

CPM math converts through the funnel: at a $2 CPM and 1% CTR, a thousand impressions cost $2 and yield 10 clicks — an effective CPC of $0.20. Buyers constantly translate between CPM, CPC, and CPA to compare traffic priced in different units against the same offer payout.

CPM buying rewards good creatives twice: a higher CTR does not just bring more clicks, it lowers the effective cost of each one, since the impressions were already paid for.

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