CPM Calculator: Calculate Cost per Thousand Impressions
Use this free CPM calculator to find your cost per mille, total ad spend, or number of impressions. Enter any two values and the third is calculated instantly. Add clicks to see your CTR and cost per click.
CPM calculator
Enter any two values — the third is calculated automatically.
CTR and CPC
Optional: add clicks to see CTR and cost per click.
How to calculate CPM
CPM (cost per mille) is the price of one thousand ad impressions. The formula is:
CPM = ad spend ÷ impressions × 1,000
For example, if you spend $500 and get 250,000 impressions, your CPM is 500 ÷ 250,000 × 1,000 = $2.
Other formulas the calculator uses
- Ad spend = CPM × impressions ÷ 1,000
- Impressions = ad spend ÷ CPM × 1,000
- CTR = clicks ÷ impressions × 100%
- CPC = ad spend ÷ clicks
What is a good CPM?
There is no single benchmark: CPM depends on the platform, ad format, country, audience, and season. Compare CPM only within the same channel, and judge a campaign by the cost of your target action — a signup, purchase, or install — rather than by CPM alone. A cheap CPM with a low CTR can end up more expensive per click than a pricier, better-targeted placement.
CPM for publishers
If you sell ad space, the same formula gives your eCPM — revenue per thousand impressions. Extension owners can earn from native banners on ExtAds, where publisher revenue is calculated on a CPM basis for unique banner views.
Learn how CPM relates to CPC, CPI, and CPA in “CPM, CPC and CPI Explained”.