CPM

CPM (cost per mille, Latin for ‘thousand’) is how much you pay for 1,000 impressions of your ad. It is the basis for billing on many social platforms such as Meta and TikTok.

Formula

CPM = ad spend ÷ impressions × 1,000

Example

A Meta campaign costs $1,800 and generates 150,000 impressions.

CPM = $1,800 ÷ 150,000 × 1,000 = $12

With a click-through rate of 1.2%, that means 1,800 clicks and a cost per click of $1.

What drives CPM

• Audience: Affluent or highly contested audiences cost more.
• Competition and season: On many platforms, prices rise noticeably in Q4.
• Placement and format: Feed, Stories, Reels or display networks are priced differently.
• Relevance: Ads that perform well are often delivered more cheaply.

CPM in lead generation

CPM is a buying metric. It tells you how expensive reach is, but not whether that reach pays off. A low CPM is only good if the people you reach also click, inquire and buy. A campaign with a $25 CPM can be far more profitable than one at $6 if it reaches the right decision-makers.

The real question is: how much revenue comes out of 1,000 impressions? LeadMetrics syncs spend and metrics of your campaigns from Meta, Google Ads, TikTok and LinkedIn and connects them with leads and deals from your CRM. In dashboards you can drill down from channel to individual ad and see whether cheap reach actually turns into deals.

Common mistakes

• Judging CPM in isolation: Without click-through rate and conversion rate, CPM tells you very little.
• Comparing platforms directly: A LinkedIn impression reaches a different audience than a TikTok impression.
• Confusing impressions with people: The same person can see an ad several times – keep an eye on frequency.