About campaign goal types
There are four types of goals available for house ad campaigns and direct sold campaigns:
1. Mediated ads (recommended for backfill)
Your ads compete in the mediation chain using an eCPM that can be optimized for backfill. You can choose how your ads will be ordered in the mediation chain using either:
- Google optimized for backfill: Use your house ads as backfill when paid ads would have negligible value.
- Manual eCPM: The eCPM value you set during campaign creation is used to place the campaign in competition against other CPM-based ad sources, including the AdMob Network, campaigns that use eCPM floors, and third-party ad networks. If your paid ads are below this eCPM value, your campaign will serve instead of your paid network ads.
Note: Though the manual eCPM is shown as a monetary value, mediated house ads are always free.
Mediated ads campaigns aren’t required to have a set end date, though you can set one if desired.
2. Number of impressions
These campaigns have defined start and end dates and specific impression goals. AdMob will speed up or slow down the delivery of ads to meet the impression goal. Impression goals are typically used for brand campaigns. Advertisers usually want to make sure that their campaign is seen a certain number of times.
3. Number of clicks
These campaigns have defined start and end dates and specific click goals. These campaigns are performance-based. For example, you would use a click goal campaign when you want to make sure to send a certain number of views to your app's page in an app store.
4. Percentage of impressions
These campaigns can also be referred to as sponsorship campaigns. Your campaign will be given first priority for the specified percentage of impressions. These campaigns have defined start and end dates but no specific impression goals. They have the highest priority, so they can use the specified share of the app's advertising inventory.
If the campaign targets multiple ad units, the campaign will serve ads for the specified percentage of impressions across each ad unit (e.g., a campaign with a "10% of impressions" goal will serve ads to 10% of impressions for each ad unit targeted by the campaign). A campaign with a 100% of impressions goal will serve ads for all impressions. Percentage of impressions campaigns use a cost-per-day (CPD) model.