eCPM floors, also known as minimum eCPMs, instructs the AdMob Network not to serve ads to that ad unit that are below the minimum eCPM you've set. You can set AdMob eCPM floors in the settings of individual ad units.
How eCPM floors work
eCPM floors apply to ads served from the AdMob Network and your bidding ad sources. Note that eCPM floors do not apply to ads served from third-party waterfall ad sources.
When you set an eCPM floor value for an ad unit, AdMob will attempt to serve an ad only if the per-impression eCPM is above the floor value that you set. If the per-impression eCPM of the ad doesn't meet the eCPM floor value, the request won't be filled by the AdMob Network or your bidding ad sources, and mediation will continue through the waterfall ad sources in the mediation group targeting the ad unit.
For example, if you set the eCPM floor at $1.00, AdMob will attempt to only serve ads with an eCPM more than or equal to $1.00.
- For CPM ads, AdMob will exclude CPM bids below the eCPM floor.
- For CPC ads, AdMob predicts the expected CPM (eCPM) for each impression based on the likelihood that the winning ad will be clicked, and then excludes the CPC ads with a predicted eCPM below the eCPM floor.
Set an eCPM floor
By default, all ad units have Google optimized floors enabled for all prices.
- Sign in to your AdMob account at https://admob.google.com.
- Click Apps in the sidebar.
- Select the name of the app you're creating this ad unit for. If you can't find it in the list of recent apps, you can click Add app to add a new app or click View all apps to search a list of all of the apps you've added to AdMob.
- Click Ad units in the sidebar.
- Click the name of the ad unit.
- Click Advanced settings.
- Click to set the eCPM floor.
- Select how you want to set the eCPM floor:
- Google optimized: Google dynamically sets your floors based on your users’ geographic locations, ad unit’s traffic, and historical data. Using Google optimized eCPM floors can help you maximize total revenue. You can choose how Google optimizes your eCPM floor by selecting one of the following methods:
- High floor (Beta): Google will maximize the higher paying ads.
- Medium floor (Beta): Google will balance higher paying ads and show rate.
- All prices: Google will maximize show rate at all price points.
- Manual floor: You manually set the value of the minimum eCPM for each ad unit. The AdMob Network won’t serve ads with an eCPM below the minimum eCPM you’ve set to the ad unit.
- Disabled: There is no eCPM floor on this ad unit.
Setting an eCPM floor value is likely to affect overall monetization. A higher eCPM floor value will likely cause a decrease in an ad unit’s show rate. You should monitor the eCPM floor placement with other ad networks to make sure you're maximizing total revenue.
Also note that setting an eCPM floor can impact the overall match rate of the AdMob Network and your bidding ad sources.
- Google optimized: Google dynamically sets your floors based on your users’ geographic locations, ad unit’s traffic, and historical data. Using Google optimized eCPM floors can help you maximize total revenue. You can choose how Google optimizes your eCPM floor by selecting one of the following methods:
Country-specific settings
Country-specific eCPM floors override the eCPM floor setting for users located in each selected country. This applies to any combination of the options listed above.
See an example setupWhat would happen if the following options were selected in AdMob?
- The eCPM floor is enabled and the default eCPM field is set to $2.
- The country-specific eCPM field for Canada is set to $3.
Answer
- For users outside of Canada, an auction will be run with a minimum eCPM of $2.
- For users inside of Canada, an auction will be run with minimum eCPM of $3.
Inaccurate floors in new ad units
If you've set up a new ad unit in AdMob with an eCPM floor, it might take a week or more for AdMob to apply the eCPM floor accurately. CPC ads can't be capped until AdMob observes enough traffic in your ad unit to calculate eCPM. If you see eCPMs in your performance reports below the eCPM floor you've set, it probably means AdMob is still learning and adjusting based on the available behavior.
You may also experience inaccurate floors if you have recently:
- Updated the value or setting of the eCPM floor applied to the ad unit
- Made changes that affect your ad unit’s traffic (e.g. causing a change in impressions, requests, etc.)
- Moved the placement of the ad unit in your app, which dissociates the current performance of the ad unit compared to historical data