Formula
CPM = Campaign cost ÷ Impressions × 1,000CPM formula
CPM, or cost per mille, is campaign cost divided by impressions and multiplied by 1,000. A $1,500 campaign delivering 250,000 impressions has a $6 CPM.
Delivered versus viewable impressions
A low delivered CPM can hide poor viewability. Compare like with like: standard CPM and viewable CPM use different impression counts.
Use CPM with downstream metrics
CPM helps diagnose auction cost and reach efficiency, but it does not measure attention, clicks or sales. Pair it with click-through rate, CPC, conversion rate and contribution value.
Assumptions
- Impressions come from the same campaign cost total.
Sources and methodology
CalcMotive publishes the formula and assumptions so you can decide whether the estimate fits your use case. See our methodology standards.