Facebook has recently condensed their interest categories during a time when changes to pixel and cookie tracking have led to advertisers to rely even more on interest-based targeting. Interest based targeting is a go to among ad creators to reach their desired target market, but it seems it may not be as accurate as you would like to believe. Interest based targeting does work to a certain degree because it’s learning about users through their activity in the app. An experiment was done by North California State University where 14 new bank slate accounts were created. Data and behavior were controlled by researchers and interests deemed by Facebook were tracked. It seemed that by simply scrolling through a page determined that the user had an interest in that subject. It also seemed that any engagement whatsoever would suggest interest to Facebook, even if that engagement was negative. It was also shown that Facebook incorrectly inferred interest when someone liked Apple the tech company, it thought they also liked apples the fruit, which could be true because apples are delicious but still it’s not the same thing. This news can be a little disheartening but also expected because interest-based targeting is a great way to target users when it works, and it still does 70% of the time. We have found that the use of custom and lookalike audiences based on website traffic and customer lists are more reliable and useful to target users. The learning phase Facebook has incorporated to serve ads more effectively is thought to be a tool to help weed out the false interests. Interest- based targeting is still a great way to reach users but defining you core audience and targeting them directly by building an audience reigns supreme and is a great way to fill in that gap.