Marketing returns
Cost per Thousand Impressions Calculator
Normalize media spending to the cost of 1,000 reported impressions for a defined campaign and placement.
Use CPM to compare exposure costs. Use CPC or CPA when your question is the cost of a click or conversion rather than an impression.
What the result means
CPM measures the price of exposure, not the value of the audience. A lower CPM can still lead to worse acquisition economics if attention, clicks, or conversion quality deteriorate.
The formula
(Media spend / reported impressions) * 1,000
Results are displayed to at most two decimal places. Calculations use the unrounded inputs.
A worked example
Put the formula to work
- Media spend (currency)
- 750
- Reported impressions (impressions)
- 150,000
CPM (input currency per 1,000 impressions): 5.00
Spending 750 for 150,000 impressions costs 5 per thousand impressions.
How to use this calculator
- Export spend and impressions from the same placement report.
- Confirm whether impressions are served or viewable and keep that definition fixed.
- Divide spend by impressions and multiply by 1,000.
Why this number matters
CPM separates the cost of buying inventory from the downstream effectiveness of creative and landing pages.
Input definitions
- Media spend (currency)
- Advertising spend for the placements and reporting dates represented by the impressions.
- Reported impressions (impressions)
- Total ad displays, not unique people reached; must be greater than zero.
Assumptions and limitations
- Impressions can include repeated exposure to the same person.
- Served impressions are not equivalent to viewable impressions or attention.
- Placement, geography, and auction conditions affect comparability.
Methodology
The default result and worked example use the same calculation functions as the interactive tool. The formula cannot verify the quality or scope of your source data.
Read our calculation methodology
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