CPM

CPM is the cost of 1,000 ad impressions, used to price and compare reach-driven advertising.

CPM prices attention, not outcomes. It's the standard currency for awareness and reach campaigns because it lets you compare media costs (a YouTube pre-roll vs. a Meta feed placement vs. a billboard's estimated reach) on the same basis, independent of whether anyone clicked or bought anything.

Rising CPMs are usually a demand signal: more advertisers competing for the same inventory, often seasonal (CPMs spike hard in India around Diwali and in the US around Black Friday/Q4 as every retailer bids for the same eyeballs at once). A CPM increase isn't automatically bad news — it's only bad if your downstream CTR and conversion rate don't move enough to absorb it.