Making money on the web is most definitely fun but to make lots of it you need to know how online monetizing platforms such as AdSense works. Terms like page views, click, page CTR, CPC, eCPM and RPM are a part of the deal.
A couple of months ago AdSense updated its interface and as it seems, one of the very key metrics in reporting, the eCPM, has been removed. Many publishers seem confused as eCPM is missing from the reports but the good thing is that we now have an alternative to it, called the RPM. In an official blog post, the AdSense team clarified that there is indeed no difference between eCPM and RPM as both the terms are referring to the same thing.
Recently, we’ve heard some questions about the difference between eCPM (effective cost per thousand impressions) and RPM (revenue per thousand impressions), as the older AdSense interface references eCPM and the newer version shows RPM. We’d like to clarify and let you know that the terms are referring to the same thing: both eCPM and RPM represent your estimated earnings for every 1000 impressions. To calculate this figure, divide your estimated earnings by the number of page views, impressions or queries that you received, then multiply by 1000. For example, if you earned an estimated $0.20 from 50 page views, then your page eCPM or RPM would equal ($0.20 / 50) * 1000 or $4.00.
eCPM or RPM = (Estimated earnings / Number of page views) * 1000
This clears everything. RPM is just a new name for eCPM and nothing much has changed. eCPM/RPM still remains the key metric for publishers to identify the performance of their ads in a specific niche.