CPM Calculator
Cost Per Mille (CPM) is the price of 1,000 advertising impressions. It is the standard unit of pricing for display, video, and social media advertising and tells you how much it costs to reach 1,000 potential viewers. This calculator works in two modes: enter your ad spend and impressions to find CPM, or enter a known CPM and impression goal to find the budget required. CPM is used by advertisers to compare the cost efficiency of different channels and placements on a common scale.
CPM formula
CPM = (Ad Spend / Impressions) * 1,000
To find budget for a target impression count: Budget = CPM * Impressions / 1,000. To find impressions for a budget: Impressions = Budget / CPM * 1,000.
Understanding CPM in context
- CPM measures reach efficiency, not engagement efficiency. A low CPM is only valuable if the audience is relevant.
- Compare CPM across channels only when targeting identical audiences; otherwise differences reflect audience quality, not just price.
- Effective CPM (eCPM) is used in performance campaigns: eCPM = (Spend / Conversions) * 1,000 / Conversion Value to normalize revenue across campaigns.
- Viewable CPM (vCPM) measures only impressions where at least 50% of the ad was visible for 1 second or more, a higher-quality metric than raw impressions.
CPM: frequently asked questions
What does CPM stand for?
CPM stands for Cost Per Mille, where mille is Latin for thousand. CPM is the cost to serve your ad to 1,000 users. A CPM of $5 means you pay $5 to reach 1,000 people, or $0.005 per impression.
How is CPM calculated?
CPM = (Ad Spend / Impressions) * 1,000. If you spend $500 and receive 100,000 impressions, your CPM is ($500 / 100,000) * 1,000 = $5.00.
What is a good CPM for digital advertising?
CPM varies widely by channel and audience. Display advertising averages $2 to $5. Social media CPMs range from $5 to $30 depending on targeting. Video CPMs typically run $10 to $30. Programmatic CPMs can be as low as $1 for broad audiences.
When should I use CPM vs CPC bidding?
Use CPM when your goal is brand awareness or maximizing reach at a fixed budget. Use CPC when your goal is direct response, as you only pay when someone takes action. CPM can be more cost-effective when your click-through rate is high.
How do I convert CPM to CPC?
CPC = CPM / (CTR * 10). If CPM is $10 and CTR is 1%, then CPC = $10 / (1 * 10) = $1.00. This lets you compare the effective cost of CPM-priced inventory against CPC bids.
Official sources
- Federal Trade Commission, Digital Advertising Disclosures: ftc.gov/business-guidance.
- U.S. Census Bureau, E-Stats: census.gov/programs-surveys/e-stats.
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.