Quick Answer: CPM is Advertiser's Cost, RPM is Your Revenue
CPM (Cost Per Mille) — the amount an advertiser pays per 1,000 ad impressions. This is the advertiser's expense. You do not receive this amount.
RPM (Revenue Per Mille) — the amount you earn per 1,000 video views, after YouTube takes its 45% cut and accounting for views that received no ads. This is your actual income metric.
CPM will always be higher than RPM. A channel with a $10 CPM earns roughly $5.50 RPM — not $10. This surprises many new creators who assume they'll receive the full CPM amount.
The CPM to RPM Formula Explained
The simplified formula is: RPM ≈ CPM × 0.55
Why 0.55? YouTube takes 45% of ad revenue. Creators receive the remaining 55%. However, RPM is typically a bit lower than this formula suggests because:
- Not every view results in a monetized ad impression (some viewers use ad blockers)
- Some views come from regions with very low advertiser demand
- Some views are on mobile with limited ad formats
Here's the math at common CPM levels:
| Advertiser CPM | Creator's 55% | Typical Actual RPM | Gap Explanation |
|---|---|---|---|
| $2.00 | $1.10 | $0.80 – $1.10 | Ad blockers, unmonetized views |
| $5.00 | $2.75 | $2.00 – $2.75 | Mixed geography |
| $10.00 | $5.50 | $4.00 – $5.50 | International views dilute average |
| $20.00 | $11.00 | $8.00 – $11.00 | High-CPM niche, some unmonetized |
Why YouTube Keeps 45%
YouTube's 55/45 revenue split has been in place since the YouTube Partner Program launched in 2007. The 45% YouTube retains covers:
- Platform infrastructure — Servers, CDN, bandwidth, storage for billions of videos
- Content moderation — Automated and human review systems
- Creator tools — YouTube Studio, Analytics, Channel Memberships system
- AdSense infrastructure — The billing, fraud detection, and advertiser management systems
- Google's sales force — The teams that sell advertising to brands
By comparison, Twitch pays streamers a 50/50 split on subscriptions, and TikTok's creator fund pays far less per view than YouTube AdSense. YouTube's 55% creator share is considered competitive in the industry — especially given that creators use YouTube's infrastructure at no cost.
Which Metric Should You Track in YouTube Studio?
Both CPM and RPM appear in YouTube Studio under Analytics → Revenue. Here's when to use each:
Track RPM for your actual earnings and income projections. RPM × (total views / 1,000) = your estimated monthly AdSense revenue. This is the number to optimize.
Track CPM to understand advertiser demand trends in your niche. If your CPM is rising, advertisers are competing more for your audience — a positive sign. If CPM drops in Q1, that's normal seasonality. If CPM drops for no obvious reason mid-year, it might indicate your content is drifting away from high-value advertiser targets.
Both metrics are found at: YouTube Studio → Analytics → Revenue tab. You can filter by time period, content, and geography to see trends.
Real Example: $8 CPM Channel — Actual Revenue Calculation
Let's walk through a concrete example. A tech review channel has:
- 100,000 monthly views
- CPM of $8 (advertisers pay $8 per 1,000 ad impressions)
- YouTube takes 45% = creator gets 55%
- RPM = $8 × 0.55 = $4.40 (in reality, approximately $3.80–$4.40 after unmonetized views)
Monthly AdSense revenue = RPM × (views / 1,000) = $4.40 × 100 = $440/month
At the same view count but with a finance channel at $15 CPM: RPM ≈ $8.25 → $825/month. The niche difference alone more than doubles the earnings from identical view counts.