In context
You upload 5,000 past purchasers as a custom audience and create a 1% lookalike in the US. Meta finds ~2.5M people demographically and behaviorally similar. Your CPA on that audience lands 20-30% below broad targeting for cold campaigns, especially in sub-$50 AOV ecom.
Why it matters
- Seed quality > seed size — 1,000 high-LTV customers beat 10,000 random visitors.
- 1% lookalikes outperform 3-5% lookalikes in most tests.
- Advantage+ Audience is the auto-built successor in 2026.
Related terms
Frequently asked questions
1% or 3% lookalike — which is better?
1% almost always wins for cold DTC. Go to 3-5% only if 1% is too small to scale.
How many seed customers do I need?
Minimum 500, ideally 2,000+. Meta suggests 1,000 for meaningful modeling.
Does iOS 14.5 hurt lookalikes?
Yes — seed signal is weaker. Compensate with CAPI + higher-quality seed (LTV-filtered).