Most of us have enough experience as consumers to know that you get what you pay for. Choosing the cheapest option — in food, clothes, cars, homes, and all the services that support our lifestyle — rarely gives us the value we want. The same goes with media. Jake Moskowitz from the Emodo Institute introduces the concept of aCPM and explains how it can help you make smarter media buying decisions.


Like vCPM, which adjusts a campaign’s CPM to account for non-viewable inventory, aCPM adjusts costs for data inaccuracy — and the resulting lost value — in media & data purchases. An aCPM applies the accuracy rate to the original CPM to calculate the cost of only the impressions bid on based on accurate data or information, knowing that there is likely to be a degree of media waste in any campaign.

For example, if you buy media for a CPM of $1 and your viewability is 50%, then the vCPM — the true value — is actually $2. The same idea goes for aCPM, but instead you’re adjusting for the accuracy of the data that led you to buy that media in the first place, making up for the media waste.

An aCPM can be adjusted for a variety of accuracy factors like segment definition, look-alike modeling, the accuracy of the POI database, and bid request filtering. The unifying purpose, however, is to create a way for you to make an apples-to-apples comparison of the segments or inventory sources you’re considering. An $0.80 CPM may look a lot more attractive than one that’s $5. But, if you apply the aCPM and find that the cost isn’t really $0.80, but $6.40 — due to the fact that the segment is made up primarily of devices or users not actively in the market to buy, perhaps due to look-alike modeling being used to significantly expand the segment — you can make a better decision to make sure you’re getting the most value for your money.