About this tool
CPM Calculator is a free, in-browser tool that works out the cost per 1,000 impressions of an advertising campaign. Pick what you want to solve for — CPM, total cost, or impressions — and the field being solved is hidden while the other two stay editable. Every figure is computed locally as you type; nothing is uploaded.
The three variables are linked by one relationship: CPM = cost ÷ impressions × 1,000. Rearranged, cost = CPM × impressions ÷ 1,000 and impressions = cost ÷ CPM × 1,000. The tool applies whichever form matches your selection and echoes the two inputs alongside the solved result.
Use it to compare media buys on a like-for-like basis, to back out the impressions a fixed budget will buy at a quoted CPM, or to price a placement. Cost and CPM are shown as currency and impressions as a whole number.
Frequently asked questions
What is CPM and how is it calculated?
CPM (cost per mille) is the cost of 1,000 ad impressions: CPM = total cost ÷ impressions × 1,000. A 500 spend that delivers 100,000 impressions has a CPM of 5.00.
How do I find the cost or the impressions instead?
Change the 'solve for' selector. Choose Cost to compute cost = CPM × impressions ÷ 1,000, or Impressions to compute impressions = cost ÷ CPM × 1,000. The field you are solving for is hidden.
Why do I get an invalid-input message?
The calculator refuses to divide by zero or use negative figures. When solving for CPM you need impressions above zero; when solving for impressions you need a CPM above zero. Fill the two visible fields with valid numbers.
Is my campaign data sent anywhere?
No. Costs and impression counts are processed entirely in your browser — the tool works offline and uploads nothing.
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