Glossary

CPM

A pricing metric calculated by dividing media cost by impressions and multiplying by 1,000.

Media BuyingFoundationAlso called: Cost Per Mille, Cost Per ThousandSource: IAB Tech Lab

Definition

A pricing metric calculated by dividing media cost by impressions and multiplying by 1,000.

Why it matters

CPM tells you what you are paying for exposure, not what you are getting for it. It is the most commonly quoted metric in a media plan and the easiest one to optimise into a bad decision.

Key consideration

A lower CPM does not mean better performance. Cheap CPM can mean low-quality inventory, poor viewability, or bot traffic. Never optimise CPM in isolation from viewability, IVT, and downstream conversion.

Related terms

Related benchmarks

APAC benchmarks for this metric are broken out by market and channel.

See CPM benchmarks →

Run the numbers

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Practitioner notes

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