CPM Calculator

Formula

CPM = (Total ad spend ÷ Impressions) × 1,000
Impressions = (Budget ÷ CPM) × 1,000
Budget = (Impressions ÷ 1,000) × CPM

How to read CPM

CPM stands for cost per mille — the price you pay for one thousand ad impressions. It is the standard buying unit for display, video, social and programmatic media, and the quickest way to compare the cost of reach across channels before performance metrics like CTR or conversion rate come into play.

A low CPM is not automatically good. Cheap impressions in the wrong placement or audience produce cheap clicks that never convert. Read CPM together with CTR and conversion rate: CPM tells you what attention costs, the other two tell you what that attention is worth.

Frequently asked questions

What is a good CPM?

It depends on channel, country, format and audience. Broad display inventory can trade for a few dollars per thousand while narrow B2B audiences on LinkedIn cost many times more. Compare your CPM against your own historical figures for the same channel and audience rather than against a single industry number.

Is CPM the same as eCPM?

No. CPM is what an advertiser pays per thousand impressions. eCPM (effective CPM) is what a publisher earns per thousand impressions, regardless of whether the ads were sold on a CPM, CPC or CPA basis. Same formula, opposite side of the transaction.

How do I convert CPM to CPC?

CPC = CPM ÷ (CTR × 10). For example, a $10 CPM with a 0.5% CTR gives a CPC of $10 ÷ 5 = $2.00. Use the CTR calculator to get your click-through rate first.

Does CPM include VAT or platform fees?

Ad platforms report CPM on media cost before tax. If you are reconciling against invoices, add VAT, agency fees and any tech fees to the cost before dividing by impressions to get a fully loaded CPM.