Metric wiki
CPM vs RPM
By Oliver Wakefield-Smith · updated July 2026
The short answer
CPM and RPM describe one impression from opposite ends of the invoice: the advertiser pays CPM before the platform's cut; the creator keeps RPM after it, spread over every view including the unmonetized ones. RPM is mathematically always lower. On YouTube the cut is published: creators keep 55% of watch-page ad revenue.
Buyer to seller: CPM down to RPM
RPM = CPM × revshare × monetized-view rate
$5.00 CPM × 0.55 × 0.8 monetized = $2.20 RPM
$10.00 CPM × 0.55 × 0.8 monetized = $4.40 RPM
$20.00 CPM × 0.55 × 0.8 monetized = $8.80 RPM
Revshare: YouTube's published 55% watch-page term. The 80% monetized-view rate is a stated input; substitute your dashboard's.
Seller to buyer: RPM back up to CPM
implied CPM = RPM ÷ revshare ÷ monetized-view rate
$4.00 RPM ÷ 0.55 ÷ 0.8 = $9.09 implied advertiser CPM
Useful for creators pricing direct sponsorships: the implied CPM is what advertisers demonstrably pay for your audience through the platform.
That reverse direction is underrated: if brands pay the platform an implied $9.09 per thousand to reach your viewers, a direct integration quoted near that rate is priced off evidence, not vibes. The podcast world runs on exactly this arithmetic with published rates (worked here).
What sits in the gap, item by item
- The platform's share: published on YouTube (45% of watch-page ad revenue) and AdSense (32%); undisclosed most other places.
- Unmonetized views: ad-free sessions, blockers, unfilled slots; they dilute RPM but never touch CPM.
- Mix effects: RPM blends every revenue stream and view type; CPM describes only sold impressions. The platform-by-platform definitions are at what is RPM.
Full waterfall with the platform mechanics: the YouTube flip side. Both ends of the same channel: YouTube buy side and YouTube earn side.