What is a lookalike audience?
How does a lookalike audience work?
You give Meta a source audience: people you already know. Meta's help says its system uses information such as demographics, interests and behaviours from that source to find new people who share similar qualities1. The aim is reach beyond the people you already have.
The source can be a Custom Audience: Meta's name for an audience of people you already have a connection with, such as a customer list or your site visitors. See that entry for how it is built.
Why does the source list matter?
A lookalike is a copy. If the original is vague, the copy is too. A list of buyers tells Meta what a customer looks like. A list of every visitor tells it what a visitor looks like. Meta's own help makes a similar point: an audience made from your best customers may do better than one that includes all of them, depending on your goals1.
That makes the source a quality decision, and a data decision. The list is your own first-party data: data a brand collects directly from its own interactions with customers, such as orders, accounts and email sign-ups. The better the list, the better the starting point.
Our view: build lookalikes from buyers rather than visitors, and ask what the source was before judging the results.
Where audiences sit in an account is covered in Meta Ads Manager account structure.
Worked example
Easily confused with
Lookalike audience vs Custom audience
People you already know. A lookalike is built from one and aims at people you do not.
Lookalike audience vs Retargeting
Ads to people who already visited your site. A lookalike reaches new people.
Lookalike audience vs Advantage+ sales campaigns
Meta's automated campaign type for sales, previously called Advantage+ shopping campaigns, in which machine learning manages audience, creative, budget, optimisation and placement. It is a campaign type. A lookalike is an audience.
FAQ
What do I need to build a lookalike audience?
A source audience: people you already know, such as buyers. Meta builds the lookalike from that source's characteristics1.
Is a bigger lookalike audience better?
Not by default. Meta's help says a closer match to the source gives a smaller audience and a looser one a broader audience, and that the quality of the source also matters1.
Sources
- About Lookalike Audiences (Meta Business Help Center)Primary source
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