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Demographic / Custom Properties


Demographic targeting requires UserDB, a data management platform that comes with the Business & Enterprise tiers. Custom Properties can be added to UserDB only by the API.


Please note: Adzerk is not providing demographic data. You need to be collecting that and sending it to UserDB. Adzerk will do the heavy lifting of using that data to determine if an ad is eligible to be shown.


Demographic Segments are loved by advertisers, who will pay more knowing that they are showing ads to a targeted audience (or will keep spending because they are seeing great performance). It's a big reason why Facebook's native ad product has seen such success.


Demographic targeting refers to targeting users based on user-given key/value pair information, like:




Male, Female


18+, 20, 40-50, etc


<$50K, $50K - $100K, $100K+

Custom Properties is a broader term that captures any user-specific info you have acquired (through onboarding process or behavioral tracking), such as:



Favorite Website

Pinterest, Hacker News

Total Times Logged Into App

1, 5, 50+

UserDB UserKeys

Adzerk saves a user's demographic data in UserDB, a data management platform for storing user-level info. All data is stored as the custom field, tied to a UserKey, which is the persistent key field in UserDB. Please refer to our UserDB documentation for more information.


Adzerk does not provide the demographic data itself. Instead, you will need to send information associated with the user to UserDB, which will store the data and then be used for ad targeting.

Using API to Add Custom Properties To A User

To tie Custom Properties data to a UserKey (the key field in UserDB), you will need to use the UserDB API Custom Property Endpoint.

Targeting Custom Properties

To target these segments, refer to our Custom Targeting and UserDB Reserved Keys docs.

The queries used to target should look like:

UserDB Custom Property Key/Value

Example Custom Targeting Query

Age: 30

$user.custom.age > 25

Gender: Female

$user.custom.gender = "Female"

FavWebsite: Pinterest

$user.custom.orientation contains "Pinterest"

Setting Up Custom Property Targeting - Flight Level

When creating flights via the Create Flight endpoint, include the Reserved Keys targeting string under the CustomTargeting parameter. You can also update CustomTargeting with the Update Flights endpoint.

You'll want to use Reserved Keys with a format of $user.custom.[Key]

An example JSON request via the endpoint is:

  "Name":"People Over 25-Years-Old",
  "GoalType": 1,
  "CustomTargeting":"$user.custom.gender = \"Male\""


Make sure to use "" before quotation marks in strings to avoid the API request breaking

Setting Up Custom Property Targeting - Ad Level

Similar instructions to the Flight level. You'd want to use the Create Ads endpoint. An example request would look like:

    "CustomTargeting":"$user.custom.age > 25"

Setting Up with UI

  • Flight-Level - Go to Flight Settings, click "Custom Targeting" on the left
  • Ad-Level - Click on the Creative in the Flights page, put in details under "Delivery Settings"


Remember: for Custom Properties Targeting to work, you will need to pass the UserKey in the user object's key field of the Decision API request. If you send the UserKey, Adzerk's Ad Decision Engine will cross-reference with UserDB when picking the right ad. If you do not send UserKeys, Custom Properties Targeting will not work.

Updated 10 months ago

Demographic / Custom Properties

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