CPM Calculator

How to use the CPM Calculator

Measure ad cost per thousand impressions. Enter campaign spend and the total number of impressions over the same dates.

Formula

CPM = spend ÷ impressions × 1,000.

Worked example

$240 spent for 80,000 impressions gives 240 ÷ 80,000 × 1,000 = $3 CPM.

Interpretation and limitations

Impressions must be positive. Impressions count displays, not unique people. The same person may see an ad several times, and a served impression is not necessarily a viewable impression.

CPM questions

Why multiply by 1,000?

CPM expresses the price for a thousand impressions, which makes small per-impression costs easier to compare.

Can I compare different campaign CPMs directly?

Use the same impression definition and consider audience, placement and results. A cheaper impression may be less valuable.

Continue your calculation

For the next step, use the CTR Calculator or the CPC Calculator. Review each tool’s input definitions before carrying a result into another calculation.

Frequently asked questions

Is this calculator free?

Yes. It runs in your browser and does not require an account.

How should I use the result?

Use the result as a planning estimate and verify business-critical decisions against your source records.