Enter what a campaign cost and the impressions it served. Get the CPM, the cost of a single impression, and how far your next budget goes at that price.
What the campaign cost.
From the ads manager, same period.
Optional. Shows the impressions it buys at this CPM.
The calculator gives you the number instantly. Leave your email and we will look at your actual accounts and send back what we would change first.
CPM is cost per mille: what you pay for 1,000 impressions. CPM = ad spend ÷ impressions × 1,000. Spend $2,500 and serve 312,500 impressions and the CPM is $8.00.
The reverse is the planning number. Impressions = budget ÷ CPM × 1,000. At an $8 CPM, $10,000 buys 1.25 million impressions. That is the reach ceiling for the budget before frequency eats into it.
Every major ad platform runs an auction for each impression, so CPM is the clearing price of attention. It rises with competition for the same audience, with narrow targeting, with premium placements and in the weeks before Black Friday and Christmas, when retail budgets crowd the auction.
Ad quality moves it too. Meta and Google both weigh predicted engagement when they price an impression, so a creative people ignore pays more to reach the same person than one they stop for.
CPM prices reach. CPC prices clicks. CPA prices outcomes. They are linked by click-through rate and conversion rate: CPC = CPM ÷ (1,000 × CTR), and CPA = CPC ÷ conversion rate.
That is why a cheap CPM is not a cheap campaign. A $4 CPM at a 0.3% CTR works out to a $1.33 click; a $12 CPM at a 1.5% CTR is an $0.80 click. Judge the buy on the cost of the result you need, then use CPM to understand why it moved.
Awareness and reach campaigns are bought on impressions, so CPM is their efficiency metric. For conversion campaigns it is a diagnostic: a rising CPM with a flat CTR means the audience got more expensive, while a flat CPM with a falling CTR means the creative stopped working.