What each metric measures
CPM (cost per mille) is the advertiser-side number: what brands pay for 1,000 monetized playbacks— views where an ad was actually shown. YouTube takes its cut after this number.
RPM (revenue per mille) is the creator-side number: your actual revenue per 1,000 total views, after YouTube's share, across every view — including the ones that showed no ad. RPM is always lower than CPM, usually by half or more, and it's the only number that predicts your payout.
Why RPM is so much lower
Two discounts stack. First, the revenue split: on long-form ads, creators keep 55% and YouTube keeps 45%. Second, not every view is monetized — ad blockers, unfilled ad inventory, and non-advertiser-friendly videos mean typically only 60–90% of views show an ad. A $10 CPM with an 85% monetized ratio nets out around $4.68 RPM.
Niche drives the spread more than anything: finance and business content can see $12–30 CPMs because the audiences are valuable to advertisers, while gaming and entertainment often sit at $2–7. Geography matters too — US, UK and Australian views pay several times more than most markets.
Which one should you track?
Use RPM to forecast income and compare your own months against each other. Use CPM to judge whether your content nicheis valuable to advertisers — and whether pivoting formats or topics could move it. YouTube Studio shows both under Analytics → Revenue.