Metrico glossary
Cost per Mille (CPM)
CPM is the advertising cost per 1,000 impressions.
Definition
CPM is primarily a delivery-price metric. It shows how expensive it was to buy impression volume in a given campaign, audience, placement, or period. A changing CPM can affect downstream economics, but it does not by itself tell you whether the creative, offer, or product generated valuable customer action.
Formula
CPM = (ad spend ÷ impressions) × 1,000
Example
$500 of spend ÷ 100,000 impressions × 1,000 = $5 CPM.
What to remember
- Compare CPM only across reasonably similar objectives and inventory.
- Lower CPM is not automatically better if traffic quality is weaker.
- Use CTR and downstream conversion evidence to interpret delivery cost.