Audience overlapping insights are must to be able to drive and scale performance campaign. Especially for very active clients who are keen to test new audiences, and focus on growth, having audience duplication insights is key to achieve growth goal.

Meta offers this tool for client https://www.facebook.com/business/help/1679591828938781, basically allowing clients to see how much duplication / audience overlap there is across multiple adgroup within the same campaign auction. This tool gives clear defined insights toward which audience is impacting the most auction cannibalisation.

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