AdMob mediation FAQ

Below are answers to some of the most frequently asked questions about AdMob mediation. 

General

Why do my house ads have a low fill rate?

Your mediation settings tell AdMob how to choose between the AdMob Network, third-party ad networks, and house ad campaigns. The eCPM value determines the order of the ad network to serve ads, with the highest eCPM value served first. That means, if AdMob network or another ad network has a higher eCPM value with 100% or close to 100% fill rate, then the other ad sources including house ad campaigns will be served less often.

If you want to serve more house ad impressions to your house ad campaigns, try the following workaround:

1. Set up an eCPM Floor for AdMob network with a reasonably high eCPM value.
2. Set up a house ad campaign with the second highest eCPM value.
3. Set the AdMob network eCPM value with the next highest eCPM value.

What this accomplishes is that AdMob network will first serve only ads that pay at least the eCPM floor value. Over time, this set up will maintain or increase AdMob network's eCPM value while the fill rate is likely to decrease, allowing the next ad source in mediation (in this case, house ad campaigns) to serve ads.

How do I delete AdMob Network from mediation?

Currently, you cannot delete the AdMob Network (default) mediation group.

My house ads aren't working

If you updated from legacy AdMob and your house ads aren't working, it is likely that you're still using legacy IDs in your apps. In order for house ads to work, you need to update your apps to use the new ad unit IDs.

How does the AdMob Network eCPM floor work?

When you set an AdMob Network eCPM floor value, the AdMob Network will return ads only if the per-impression eCPM is above the floor value that you set. If the per-impression eCPM does not meet the floor value, the request will not be filled by the AdMob Network and mediation will continue as normal.

How does eCPM floor work with other ad networks during mediation?

The AdMob Network will continue to make requests in the order of the highest eCPM to lowest eCPM. The eCPM floor only applies to the AdMob Network. For all other ad network line items, provide a manual eCPM or optimize the ad networks to adjust their own eCPMs.

Optimization

Which third-party ad networks support optimization?

Learn more about the ad networks that support optimization.

How does AdMob obtain data from third-party ad networks?

This varies for each ad network, but we either use APIs or screen-scraping to access the data. There are some ad networks that don't permit either of these methods, so they won't be included as part of this feature at this time.

Do I need to update the SDK to use ad network optimization?

No, but we always recommend that you update to the latest SDK.

What data does AdMob look at to determine the CPM?

AdMob looks at the reporting data from each ad network for each ad unit based on the platform and country (if available). AdMob collects data daily and updates the mediation stack whenever there's new information from the ad network.

Can I mix and match optimization, manual eCPM, and floor across different ad networks?

Yes, it's possible to use different combinations of optimization, manual eCPM, and AdMob Network floors across ad networks in the same mediation group.

Note: Some ad networks may not support optimization, and setting a floor is only available for the AdMob Network. 

What happens if AdMob can't retrieve the eCPM data from an ad network?

If AdMob can't obtain the eCPM data from an ad network for more than seven days, the user interface will show an alert message to let you know that there's an issue. AdMob will continue to use the last eCPM for that ad network. 

Why is the network status still "Pending optimization"?

When you enable optimization for a third-party ad network in mediation, AdMob begins analyzing your app's traffic to understand the best way to optimize its eCPM. During this analysis period, you may see the "pending optimization" status appear in the ad networks table. 

AdMob continuously optimizes eCPM based on the latest data available, so you may occasionally see the "pending optimization" status even after the initial analysis is complete. For example, if there is insufficient traffic from an ad network over several weeks, AdMob may determine that better quality data is needed to accurately calculate the eCPM. Optimization will be re-enabled once the ad network's traffic increases and AdMob has better data to analyze. 

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 fill rate. You should monitor the eCPM floor placement with other ad networks to make sure you're maximizing total revenue.