CPM vs. vCPM
Can someone please explain the difference between CPM and vCPM. I know CPM focuses on impressions and vCPM focuses on viewable impressions, but I am hoping for a more in depth answer.
Hi Green B, there's really not much more to it than what you've already said.
With CPM you bid based upon 1,000 impressions and some of those impressions may be recorded for Ads that weren't actually visible to the viewer, e.g. those "below the fold".
With vCPM, you bid upon, and are only charged for, impressions that are measured as visible to the user (Google defines "visible" as 50% or more of your Ad showing for 1 second or longer).
Although vCPM seems like the obvious choice, you can end up paying more for 1,000 impressions since they generally have to win more auctions, etc. so you'll have to test with your own Account to see which is the better option.
More about Viewable Impressions: https://support.google.com/adwords/answer/3499086?hl=en
CPM:- you pay based on the number of impressions (when your ads are shown) whether your ads are viewed or not. Simply, you are charged when the ad is loaded on a page and not necessarily if a user actually saw the ad.
vCPM: you pay per viewable impressions, Google records viewable impressions when your ad is 50% visable on the screen for at least one second or longer.