How to calculate CPM
CPM (cost per thousand impressions) is calculated by taking the total cost of an advertising campaign, dividing it by the number of impressions (views) it received, then multiplying by 1,000: CPM = (cost ÷ impressions) × 1,000. For example, if a display ad campaign costs $500 and gets 200,000 impressions, the CPM is ($500 ÷ 200,000) × 1,000 = $2.50. This means each thousand views cost $2.50 to reach. Use the calculator above to find CPM, total cost, or impressions reached from any two of the three values.
CPM vs CPC vs RPM
Three common advertising metrics are often confused. CPM (cost per thousand impressions) is what advertisers pay per 1,000 ad views, regardless of clicks. CPC (cost per click) is what they pay only when someone clicks the ad — better for direct response campaigns where clicks matter. RPM (revenue per thousand impressions) is what publishers earn per 1,000 views on their site, regardless of clicks. A publisher earning $2 RPM receives $2 per 1,000 pageviews; an advertiser paying $2.50 CPM spends $2.50 per 1,000 ad views to reach similar traffic. Different campaigns use different models depending on the goal.
What counts as a good CPM?
A good CPM varies widely depending on the industry, audience, ad format, placement, and season. Rates in technology and finance are typically higher than in other sectors. Premium placements above the fold cost more than below-the-fold placements. Seasonal peaks (like the holiday shopping period) see higher rates. Targeted, smaller audiences command higher CPMs than broad, untargeted campaigns. CPM rates vary significantly based on your specific ad network, audience targeting, and placement quality—factors that matter more than industry benchmarks. The best benchmark is your own historical data and the rates offered by the specific ad network or publisher you're working with.