Lookalike Audience

What is a lookalike audience?

A lookalike audience is an ad audience where the platform finds new people who resemble a source group (a “seed”) you choose yourself — typically a custom audience of buyers, email contacts, or visitors. The platform analyzes shared traits in the source and builds a larger audience with a similar profile and behavior. On Meta you set a size from 1% to 10% of a chosen market, where 1% most closely resembles the source, while higher percentages increase reach at the cost of precision.

Why does a lookalike audience matter?

Lookalikes are the primary way to find new customers (prospecting) in paid social, as opposed to retargeting, which reaches people who already know you. Quality depends on the source: a seed of 1,000–50,000 of your best customers produces better results than a broad list of all visitors. A strong lookalike can lower your customer acquisition cost and improve your ROAS, because ads are shown to people more likely to buy.

Common use cases

• Build a lookalike from your highest-value buyers rather than all customers.
• Create a lookalike of email subscribers or people who added to cart.
• Test a 1% lookalike against a 3–5% lookalike to find the balance between precision and reach.
• Exclude existing customers so the prospecting budget only reaches new users.

Shopify perspective

Connect the Facebook & Instagram channel in Shopify so your pixel and Conversions API send purchase and behavior events to Meta. That data keeps the custom audiences that lookalikes are built from up to date. On Meta you no longer pick a country during creation itself — geography is handled at the ad set level, so the same lookalike can be used across markets. Keep a clean source (e.g. only high-value buyers), because a lookalike’s precision is never better than the data it is built on.