Lookalike audiences are made up of users with similar characteristics to an existing Matched audience. When you target a Lookalike audience, you reach new, qualified prospects with high conversion potential. You’ll select the source audience, choose how similar the new audience should be to the existing one, and specify the desired audience size to generate the Lookalike audience.

Lookalike audiences are highly efficient. We recommend this audience type when your goal is to reduce waste and improve campaign performance. Certain advertisers may wish to create Lookalike audiences when they’re aiming to lower their data costs. It’s also especially valuable for campaigns with smaller budgets that have less room for test-and-learn spending.

Review this article for more details and requirements, then refer to Create or manage a Lookalike audience to get started.

All advertisers are eligible to create and target Lookalike audiences. The following conditions must also be met before an advertiser or campaign becomes eligible for Lookalike audience creation and targeting:

*Advertiser vertical: Specialty advertisers are eligible to create and target Lookalike audiences based on audiences that include only non-Healthcare and non-Political data. Healthcare advertisers may be eligible to create and target them based on audiences that include Specialty and/or NPI data. Political advertisers may be eligible to create and target them based on audiences that include Specialty and/or voter audience data.

**Compatible audience type: Campaigns typically support targeting multiple audience types. Healthcare advertisers should note that a single campaign, however, can never target both NPI-based and non-NPI-based audiences.

***Audience creation date: While you can target or block a Lookalike audience that you created more than one year ago, we recommend creating a new one to ensure it includes the latest Reach data.

You can review a Lookalike audience’s status on the Lookalike Audience page of the Audiences app. Refer to Review a Lookalike audience for more information on how to access this page.

When you select one or more Matched audiences to base a new Lookalike audience on, we’ll remind you of those audiences’ Match Rates. A Match Rate represents the percentage of users whose digital identities we were able to correlate to the identifiers that you included in your Matched audience’s source file(s). The average match rate on the IQM platform is 80%.

Refer to Matched audience key terms and concepts: Records, Match Rate, and Reach for more information.

In campaign reporting, Reach represents the number of unique individuals who were exposed to your ad. In Lookalike audiences, however, this metric represents the total targetable audience (unique users) that you can potentially reach by targeting it. Note that the actual addressable audience will become smaller as you apply additional targeting rules and other settings to your campaign.

When you create a new Lookalike audience, we’ll prompt you to let us know how similar the new audience should be to the existing Matched audience you selected, and to specify the desired audience size.

The relationship between these two settings is inversely proportional. This means that a highly similar audience will be smaller in size, and a less similar audience will be larger in size. Keep this relationship in mind when you choose your Lookalike audience settings to help ensure you strike your preferred balance between scale and value.