Paid Advertising
Lookalike Audience
A lookalike audience is a targeting group that an ad platform builds by finding new users who share traits with a source audience you provide, such as your customers or website visitors. It lets advertisers reach fresh prospects who resemble people already valuable to the business.
Why it matters
Lookalikes let you scale beyond known audiences while keeping targeting grounded in real customer data, which often improves prospecting efficiency. They are a primary tool for finding new buyers at the top of the funnel.
How it is measured
Lookalikes are created from a seed or source audience (customer list, pixel data, or engagers) and sized by similarity, for example a tighter 1% match versus a broader percentage. Quality is judged by the source data and by resulting conversion rate and CPA.
Typical benchmarks
A higher-quality, larger seed audience generally produces stronger lookalikes; tighter similarity percentages narrow reach but often improve relevance.
Frequently asked questions
How big should my source audience be?
Most platforms recommend a seed of at least a few thousand people, ideally your best customers. A larger, higher-intent source produces more accurate lookalikes than a small or low-quality one.
What is the difference between a 1% and a 10% lookalike?
A 1% lookalike targets the people most similar to your source, giving tighter relevance but smaller reach. A 10% lookalike is broader and larger but less precise. Many advertisers test several tiers.
How is a lookalike audience different from retargeting?
A lookalike finds new people similar to your customers. Retargeting re-engages people who already interacted with you. Lookalikes expand reach; retargeting deepens it among known prospects.