Lookalike Audience
A lookalike audience is a new group of people the ad platform finds because they resemble an existing source audience — your customers, site visitors, or best leads. It's a primary way to scale prospecting beyond retargeting.
Also called: Similar audienceFormula
Lookalike = platform models new users similar to a seed audienceExample
Upload your top 1,000 customers as a seed; Meta builds a 1% lookalike of the users most similar to them to target with prospecting ads.
Why it matters
Lookalikes let you find cold audiences that behave like your best customers, giving prospecting a warm-start. Quality depends heavily on the seed — feed it high-value customers, not all traffic.
Put these metrics to work
AdPlus plans, launches, and optimizes campaigns across 12 ad networks from one screen — and tracks every metric here for you. Free to start, no card.
FAQ
What's a good lookalike size?
Smaller percentages (1%) are more similar to your seed and higher-intent; larger ones (5–10%) reach more people but are broader. Many advertisers start narrow and widen as they scale.
How big should the seed audience be?
Most platforms recommend at least ~1,000 quality source records; more (and higher-value) seeds generally produce better lookalikes.