How to calculate CPM
Divide the campaign cost by recorded impressions, then multiply by 1,000. Use cost and impressions from the same platform, campaign scope and reporting period.
CPM = campaign cost ÷ impressions × 1,000Free media planning calculator
CPM calculator — cost per thousand impressions
Calculate cost per thousand impressions, or work backwards to estimate campaign cost or impression volume from two known values.
CPM—
Use the same currency for cost and CPM. The calculator does not assume a currency.
How to use the result
CPM makes impression costs easier to compare across media plans.
A lower CPM is not automatically better. Placement quality, audience relevance, viewability, frequency and the campaign objective determine whether those impressions are useful.
Official guidanceGoogle Ads Help: CPM definition
- 01
Enter clean inputs
Use values from the same campaign, platform and reporting period so the result answers one clear question.
- 02
Check the output
Treat the calculation or formatted list as a working aid. Review the source data, naming and campaign context before using it.
- 03
Save the decision
Copy the result into the campaign plan or reporting note together with the date, data source and any important limitation.
Formula, example and common questions
Use the number in context.
These notes explain what the calculation means, how to reproduce it and where a simple metric can become misleading.
CPM calculation example
If a campaign costs 15,000 and delivers 2,500,000 impressions, its CPM is 6 in the currency used. That number measures exposure cost, not attention, leads or sales.
Common mistakes to avoid
- Mixing cost from one date range with impressions from another.
- Comparing CPM across placements without considering viewability, audience quality or format.
- Treating impressions as unique people when the same person may see an advert more than once.
- Choosing the lowest CPM even when the placement does not support the campaign objective.
Frequently asked questions
CPM calculator — cost per thousand impressions FAQs
What does CPM mean?
CPM means cost per thousand impressions. It expresses what an advertiser paid, on average, for every 1,000 recorded ad impressions.
How do I calculate CPM?
Divide campaign cost by impressions and multiply by 1,000. A cost of 1,000 across 200,000 impressions produces a CPM of 5.
Is CPM the same as CPC?
No. CPM measures cost per 1,000 impressions, while CPC measures average cost per click. The better planning metric depends on the campaign objective.
What is viewable CPM?
Viewable CPM is based on viewable impressions rather than every served impression. Platform definitions and measurement rules should be checked before comparing reports.
Can this calculator estimate impressions from a budget?
Yes. Select Impressions, then enter campaign cost and expected CPM. The result is a planning scenario, not a delivery guarantee.