Cost Per Mille Variations
Paid MediaAlso: CPM Variations · vCPM · CPM vs vCPM vs tCPM
Quick definition
Cost Per Mille (CPM) is the price of one thousand ad impressions. Its variations, standard CPM, viewable CPM (vCPM) and target CPM (tCPM), change what counts as a billable impression. Standard CPM charges for any served impression. vCPM only charges for ones a person could actually see.
Run this twice on the same campaign, once with total served impressions and once with viewable impressions only, and compare the gap. A large gap usually points to a placement or inventory quality problem worth investigating.
How it varies across Australia
CPM in the Australian market moves with the media type more than with the variant itself. Video and connected TV inventory sit well above standard display, and vCPM campaigns often report a higher rate than standard CPM for the same placement because the unviewable impressions are stripped out before pricing.
Compare paid media benchmarks across Australian industries →The three common variants
Charges for every impression the ad server records, viewable or not.
Broadest, usually cheapestOnly bills for impressions that met a viewability threshold.
Narrower, usually higher rateA bid strategy where you set a desired average price and the platform manages delivery toward it.
Average, not guaranteedWhat it actually means
Cost Per Mille (CPM) is the oldest pricing model in digital advertising and it still hides a real argument underneath a simple formula. The formula never changes: spend divided by impressions, multiplied by 1000. What changes is what counts as an impression worth charging for.
Standard CPM charges for every impression the ad server logs, whether or not a human eye landed on it. Viewable CPM (vCPM) only bills for impressions that met a viewability standard, usually a percentage of pixels on screen for a minimum duration. Target CPM (tCPM) lets you set a price you want to pay and the platform manages delivery to hit it, similar in spirit to target CPA bidding but for impressions instead of conversions.
The confusion starts because people compare CPM across variants like they're the same currency. A standard CPM of ten dollars and a vCPM of fifteen dollars are not telling you vCPM is more expensive. They're telling you the vCPM campaign already threw out the impressions nobody could see, so the remaining ones cost more per thousand because there are fewer of them.
Reach, frequency and click-through rate (CTR) all sit downstream of which CPM variant you're buying. Get the variant wrong in your comparison and every downstream metric looks distorted.
A cheaper CPM that nobody saw is not a cheaper CPM. It is a discount on nothing.
How to calculate it
CPM = (Total spend divided by total impressions) multiplied by 1000
Worked example. You spend $2,000 on a display campaign that serves 400,000 impressions. Standard CPM = ($2,000 divided by 400,000) multiplied by 1000 = $5. If only 250,000 of those impressions were viewable, vCPM = ($2,000 divided by 250,000) multiplied by 1000 = $8. Same spend, same campaign, two very different numbers depending on which impressions you count.
The Australian context
Australian advertisers buying connected TV and video inventory often see vCPM reported as the default rather than an option, since major platforms have shifted viewable measurement toward standard practice for video. For display and social, standard CPM is still common in vendor reporting, so cross-vendor comparisons need a manual check on which variant each report is using before any conclusion gets drawn about which channel is cheaper.
Where people get this wrong
Related terms
Common questions
What does CPM stand for?
Cost Per Mille, from the Latin word for thousand. It's the cost of serving one thousand ad impressions, calculated as total spend divided by impressions, multiplied by 1000.
Is a lower CPM always better?
No. A low CPM often means lower quality inventory or impressions that weren't actually viewable. Judge CPM alongside click-through rate and conversion outcomes, not as a standalone win.
What's the difference between CPM and vCPM?
Standard CPM charges for every served impression. Viewable CPM (vCPM) only charges for impressions that met a viewability standard, usually a minimum percentage of the ad visible on screen for a set duration. vCPM is a smaller, more filtered pool of impressions.
Should I choose target CPM bidding?
Target CPM works well when you want predictable average pricing and are optimising for reach or awareness rather than clicks or conversions. It's a bid strategy that aims for an average, it doesn't cap individual auction prices.
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About New Rebellion
New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.
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