Our API allows you to build the target Custom Audiences from customer information. This includes email addresses, phone numbers, names, dates of birth, gender, locations, App User IDs, Page Scoped User IDs, Apple’s Advertising Identifier (IDFA), or Android Advertising ID.
As the owner of your business’ data, you are responsible for creating and managing this data. This includes information from your Customer Relationship Management (CRM) systems. To create audiences, you must share your data in an hashed format to maintain privacy. See Hashing and Normalizing Data. Facebook compares this with our hashed data to see if we should add someone on Facebook to your ad’s audience.
You can add an unlimited number of records to an audience, but only up to 10000 at a time. Changes to your Custom Audiences don’t happen immediately and usually take up to 24 hours. The number of records you request to remove and/or the number of Custom Audiences your account contains will increase the amount of time it takes to process this request.