1. What Is CPM?
CPM means Cost Per Mille, where mille means one thousand. In advertising, CPM generally describes the amount advertisers pay per thousand ad impressions.
CPM is therefore primarily an advertiser-side metric. It does not represent the amount a creator receives for every thousand video views.
The distinction matters because an advertiser can pay for impressions while a creator's revenue is affected by YouTube's revenue-sharing arrangements and the number of views that actually generate monetized playback.
2. What Is RPM?
RPM means Revenue Per Mille. It is a creator-oriented metric that expresses revenue earned per 1,000 views after applicable revenue-sharing effects and across the relevant views.
A simplified calculation is: RPM = estimated revenue divided by total views, multiplied by 1,000.
Because RPM relates revenue to total views rather than only advertising impressions, it can be substantially lower than an advertiser-facing CPM.
3. Why RPM and CPM Are Different
CPM can describe advertising value before creator revenue is calculated. RPM instead looks at creator revenue relative to views.
Not every view necessarily produces an advertisement. Some viewers may not receive an ad, some videos may have limited advertising availability, and different viewers can have different advertising markets.
This means a high CPM does not automatically translate into the same numerical RPM.
4. Factors That Affect RPM
Audience geography can affect advertising demand because advertisers compete differently across markets.
Content category can also influence advertiser demand. Topics with strong commercial intent may attract different advertising bids from entertainment or general-interest content.
Seasonality matters as advertising budgets change throughout the year.
Viewer behavior, monetized playback, video format, advertiser suitability, and other factors can also affect realized revenue.
5. Using RPM Correctly
RPM is most useful when comparing your own channel or videos over time under reasonably similar conditions.
A sudden change in RPM does not necessarily mean the quality of your content changed. Audience geography, traffic sources, advertiser demand, content mix, and seasonality can all change.
Creators should therefore examine RPM alongside views, watch time, audience geography, traffic sources, and content performance rather than treating it as a standalone score.