Cost-per-mile (CPM) advertising networks are networks that pay publishers a set amount for every 1,000 page impressions. The ads will show up right on the website itself or will manifest as pop-up or pop-under ads. Choosing the best CPM advertising networks depends on much more than how much the network pays per impression. Other important considerations, especially if the publisher wants to keep his website audience, are the quality of the ads, the visitor threshold of the CPM network, whether CPM advertising networks can run simultaneously, and whether the networks accept the website’s country of origin.
Ad quality is always a question and consideration when choosing CPM advertising networks or any other advertising schema. Ads that appear on the page are generally considered more natural and less annoying than pop-up or pop-under ads. What the ad itself is saying also may help keep visitors or push away the website’s intended audience. For example, if the CPM network shows adult ads but the website is supposed to be kid-friendly, this can alienate the audience.
Most, but not all, CPM advertising networks have a visitor threshold that publishers must exceed to be accepted into the network. If the threshold is higher, it is generally regarded that the publisher will be paid more and the ads will be of a higher quality. This threshold is very strict, so if the website owner has a website garnering 600 impressions per month and is trying to apply for a CPM network with a 10,000 impression threshold, the network will not accept the publisher.
CPM advertising networks are generally very fussy about what countries they will service. This is either because advertisers prefer some countries over others or that some countries will not generate the same profit as advertising in other countries would. The publisher should — prior to signing up — check the terms and see if the CPM network is willing to show advertisements on the publisher’s website.