Dark posts are a Facebook post type promoted as ads to a specific targeted audience. These posts will not show up on your standard timeline like a boosted or sponsored post but will only appear on the newsfeed of a selected set of users. As dark posts are not published like a formal ad, they are also known as ‘unpublished posts.’ Organically, users cannot find these posts. Dark posts are best for A/B testing or split testing.
Example
As a vegan pizza chain, dark posts can precisely help you go in front of users who are either students residing in Boston or middle-aged working women who order pizza and are preferably vegan. Each type will see an ad specifically designed for them.

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