To get the most out of your Facebook ads spend, you need to laser-focus your ads (because there’s no point in reaching audiences that are unlikely to convert for you).
Facebook has a massive load of targeting and ad demographic options - with one of the best ads targeting options being Interests-Based Audiences. This option allows you to target people specifically interested in a subject related to your product or business.
However, when Lookalikes Audiences were given a major update in 2018, marketers began debating whether the human brain is better than the Facebook algorithm at picking the right audience for ads.
To find an answer, the guys at Ad Espresso ran an experiment investing $1,000 of ad spend split evenly between interests and lookalikes.
For the experiment, they ran a conversion campaign to get registrations for their next webinar. The Facebook image ad took people through to a landing page. Then, when the user filled in their details, they fired the Complete Registration pixel event.
That pixel fire was counted as the conversion.
The lookalike audience was the clear winner with a 13% lower CPA (cost-per-action) as well as a better clickthrough rate and cost per click.