It tells a publisher how much revenue they earn for every one thousand ad impressions shown in their app. Although the word cost appears in the name, eCPM is a revenue metric used by publishers to judge the strength of their inventory and by networks to rank and pace campaigns.
CPM is what an advertiser agrees to pay for one thousand impressions.
eCPM is what a publisher actually earns per one thousand impressions across all demand sources and pricing models.
Think of CPM as the sticker price on the buyer side and eCPM as the blended revenue rate on the seller side. eCPM moves with supply, demand, fill, format, and user behavior.
Formula
eCPM = (Total ad revenue ÷ Total impressions) × 1000
Example
Your app earned 700 dollars from ads and served 200,000 impressions.
eCPM equals 700 divided by 200,000 times 1000 which is 3.5 dollars.
You earn three dollars and fifty cents for every one thousand impressions.
Monetization insight
Reveals which placements, formats, and geos bring the most revenue.
Pricing power
Higher eCPM signals quality and allows stronger floors and direct deals.
Iteration feedback
UI or content changes that lift eCPM likely improved attention and intent.
Forecasting
Stable eCPM paired with traffic forecasts gives a clean revenue plan.
Advertiser value
High eCPM campaigns tend to win more auctions and scale faster.
An eCPM floor is the minimum CPM a buyer must meet to win your impression.
Use floors by geo, device type, format, or placement. Review often. Too high and you lose fill. Too low and you leave money on the table. In pure in app bidding, smart floors still help but the auction does much of the work.
Grow demand
Connect multiple networks, exchanges, and bidders. Add regional specialists. Use mediation with fair auction logic.
Tune placements
Test position, size, and frequency caps. Keep ads clear and consistent with the flow of the app. Avoid clutter.
Pick formats that fit moments
Rewarded video for value exchange, interstitials at natural breaks, native for feeds, playables for games.
Reduce latency
Cache creatives where allowed. Optimize SDK calls. Monitor time to first impression and viewability.
Use smarter pricing
Set adaptive floors by country and format. Create direct packages for top advertisers. Offer first look or programmatic guaranteed where it makes sense.
Protect quality
Block low quality sources, suspicious sites, and invalid traffic. Clean supply raises bid density and long term eCPM.
Mixed CPM deals
Two million impressions at two dollars CPM and two million at one dollar CPM.
Revenue equals four thousand plus two thousand which is six thousand.
eCPM equals six thousand divided by four million times one thousand which is one dollar and fifty cents.
Network fee effect
Advertiser pays two thousand dollars for one million impressions. Exchange takes ten percent. Publisher receives one thousand eight hundred dollars.
eCPM equals one point eight dollars, not two.
How much a publisher earns for every one thousand ads shown.
CPM is what buyers pay. eCPM is what publishers earn after fill, fees, and performance.
Yes for revenue, but watch for drops in retention or session length caused by aggressive ad load.
It depends on country, category, and format. Benchmark against your own history and near peers, not a universal number.
Review weekly for active markets and always before seasonal spikes. Use data, not guesswork.
Auctions set the price, yet thoughtful floors and deal tiers still protect value on scarce or premium inventory.
Yes, but include experience cost. A format with higher eCPM that hurts retention may not maximize total revenue.