Lookalike Audience is a feature that allows advertisers to target people who are similar to their existing matched audience. It works by analyzing data on the advertiser's current customers and identifying common characteristics.

Lookalike Audience can be defined by specifying the target audience size and similarity percentage. The target audience size determines the number of people you want to reach, while the similarity percentage determines how closely the Lookalike Audience should match your existing customers.

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