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CPM calculator

Enter any two of ad spend, impressions and CPM and get the third, with the formula worked out using your numbers. Publishers can switch to RPM mode.

Your CPM

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Enter any two values.

How to calculate CPM

CPM means cost per mille, the price of 1,000 ad impressions ("mille" is Latin for thousand). It's how Meta, TikTok, YouTube, display networks and programmatic platforms usually price ads, and it's the easiest way to compare the cost of reach across platforms.

The CPM formula

CPM = ad spend ÷ impressions × 1,000
Impressions = ad spend ÷ CPM × 1,000
Ad spend = CPM × impressions ÷ 1,000

Worked example

You spent $750 and your ads were shown 120,000 times. $750 ÷ 120,000 = $0.00625 per impression. Multiply by 1,000 and your CPM is $6.25.

How to find your CPM in an ads account

Most platforms show CPM as a column, but you can always work it out from two numbers every dashboard has: amount spent and impressions for the same date range. Make sure both come from the same campaign and dates, or the result won't mean much.

CPM vs CPC vs RPM

CPM: what an advertiser pays per 1,000 impressions.
CPC: what an advertiser pays per click. CPC = CPM ÷ (CTR × 10), so a better click-through rate makes every click cheaper even on CPM billing.
RPM: what a publisher earns per 1,000 page views or impressions. Same formula, using earnings instead of spend.

Need CPC, CTR or CPA too? The ad metrics calculator works out all of them from whatever numbers you have.

FAQ

CPM questions

Can't find what you need? Ask us directly.

How do you calculate CPM?

CPM = total ad spend ÷ total impressions × 1,000. For example, $500 spent on 100,000 impressions is $500 ÷ 100,000 × 1,000 = a $5.00 CPM. CPM stands for "cost per mille", where mille is Latin for thousand.

How do I find how many impressions my budget will buy?

Impressions = budget ÷ CPM × 1,000. At a $5 CPM, a $1,000 budget buys about 200,000 impressions. Enter your budget and expected CPM above to work it out.

What is a good CPM?

There is no single good number. CPM varies widely by platform, country, audience, ad format and time of year, and it usually rises in the fourth quarter as advertisers compete for the holidays. Compare your CPM with your own past campaigns, and judge it together with click-through rate: a higher CPM with a much better CTR can still mean cheaper clicks.

What is the difference between CPM and CPC?

CPM is what you pay for 1,000 impressions, whether or not anyone clicks. CPC is what you pay per click. They are linked by click-through rate: CPC = CPM ÷ (CTR × 10) when CTR is a percentage. So a $10 CPM with a 1% CTR works out to $1.00 per click.

What is RPM, and how is it different from CPM?

RPM (revenue per mille) is the publisher's view: earnings ÷ page views (or impressions) × 1,000. CPM is what advertisers pay; RPM is what a site or channel earns per 1,000 views after the platform's share. Switch the calculator to RPM mode to work it out.

Is eCPM the same as CPM?

Effective CPM (eCPM) uses the same formula, but applied to results from any pricing model. If you paid per click or per action, eCPM = total cost (or revenue) ÷ impressions × 1,000 tells you what that equated to per 1,000 impressions, so you can compare campaigns fairly.