Meta Ads glossary

What Is Cost Per Mille (CPM)?

Definition

CPM is the average cost to deliver 1,000 ad impressions.

How Cost Per Mille (CPM) Works

CPM equals ad spend divided by impressions, multiplied by 1,000. It reflects the price of distribution before clicks or conversions occur.

A Simple Example

If a campaign spends $500 for 100,000 impressions, its CPM is $5.

Why Cost Per Mille (CPM) Matters

CPM helps separate changes in the price of reach from changes in click-through rate and conversion rate.

Common Misreading

A low CPM can be paired with poor attention or weak buyers. Cheap distribution is only useful when the audience and creative produce business results.

Go deeper

Continue with the practical guide

The glossary gives you the definition. The guide covers the decisions and implementation in more depth.

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