CPM is the price of a thousand ad impressions (M is the Roman numeral for 1,000). It is how display, video, social and podcast inventory is priced, and the common currency for comparing channels. This calculator solves the CPM equation for whichever number you are missing, then carries the spend through to cost per click and cost per conversion.
How it is calculated
- CPM = cost ÷ impressions × 1,000.
- Cost = CPM × impressions ÷ 1,000.
- Impressions = cost ÷ CPM × 1,000.
- Clicks = impressions × CTR; CPC = cost ÷ clicks. Conversions = clicks × conversion rate; CPA = cost ÷ conversions.
Example
A $2,500 campaign delivers 500,000 impressions: CPM = 2,500 ÷ 500,000 × 1,000 = $5.00. At a 0.5% CTR that is 2,500 clicks at $1.00 each; at a 2% conversion rate, 50 conversions at $50 each. If the same budget bought 250,000 impressions the CPM would double to $10, and every downstream cost would double with it unless the audience clicked more.
Reading a CPM
A low CPM is only good if the impressions are seen by the right people. Cheap open-web display often runs $1–3 with click rates near 0.1%; a $40 LinkedIn CPM can be the cheaper lead if the audience converts. Compare channels on CPA or return, and use CPM to size budgets and negotiate rates. Also check whether a quoted CPM is per served or per viewable impression (vCPM); viewable counts only ads at least half on screen for a second, and costs more per thousand.
Frequently asked questions
How do you calculate CPM?
Divide the total cost by the number of impressions and multiply by 1,000. $500 for 100,000 impressions is a $5 CPM.
What is a good CPM?
Depends on the channel: $1–5 for open-web display, $5–15 on Facebook and Instagram, $10–30 on YouTube, $30–80 on LinkedIn. A good CPM is one that produces an acceptable cost per result, not the lowest number.
What is the difference between CPM and CPC?
CPM prices impressions; CPC prices clicks. They are linked by the click-through rate: CPC = CPM ÷ (1,000 × CTR). At a $5 CPM and 0.5% CTR the CPC is $1.
What does vCPM mean?
Cost per thousand viewable impressions: only ads that were at least 50% on screen for at least one second count. It is higher than plain CPM for the same campaign but reflects ads people could actually see.
How many impressions can I get for my budget?
Budget ÷ CPM × 1,000. $2,000 at a $8 CPM buys 250,000 impressions. Choose "Solve for impressions" above.
Sources
By Calcelate Team. Formula from the sources above.
- 2026-09-14 · Formula and texts checked