Glossary · Platforms and measurement
CPM
Cost per mille: what you pay for every 1,000 times an ad is shown.
In detail
CPM stands for “cost per mille” (mille is Latin for thousand). If a space costs a CPM of $4, showing the ad 1,000 times costs $4, whether or not anyone clicks.
It is calculated as: cost ÷ impressions × 1,000. It is useful for comparing the cost of reaching an audience across different sites or formats.
Example
You spend $200 and get 50,000 impressions: CPM = 200 ÷ 50,000 × 1,000 = $4.