A lookalike audience is a way your ads can reach new people who are likely to be interested in your business because they share similar characteristics to your existing customers.
A lookalike audience uses an existing Custom Audience you select for its source audience. To create a lookalike audience, our system leverages information such as demographics, interests and behaviors from your source audience to find new people who share similar qualities. When you use a lookalike audience, your ad is delivered to that audience of people who are similar to (or “look like”) your existing customers.
When you create your lookalike audience, you can use a percent range to choose how closely you want your new audience to match your source audience. The size you choose depends on your goals. Smaller percentages more closely match your source audience, but larger percentages create a bigger, broader audience.
We generally recommend a source audience that has between 1,000-5,000 people. However, the quality of your audience also matters. For example, you may get better results depending on your goals if you use an audience made from your best customers rather than one that includes all your customers.