A Lookalike Audience is a targeting group created by ad platforms that finds new people who share similar characteristics with your existing customers, website visitors, or engaged users. You provide a "seed audience" - like your email list, past purchasers, or high-value customers, and the platform's algorithm analyzes thousands of data points to find new prospects who match those patterns. This solves the cold prospecting challenge by letting platform data identify your ideal customer profile instead of manually guessing interests and demographics.

Why Lookalike Audiences Matter

Lookalikes bridge the gap between retargeting (limited scale) and cold prospecting (expensive learning phase). Manual interest targeting requires guessing which demographics and interests define your customer, but lookalikes let the platform's data reveal patterns you'd never identify manually - like "people who bought from you also engage with home improvement content on weekends and watch cooking videos." When built from high-quality seed audiences, lookalikes typically deliver CPA 30-50% lower than broad interest targeting while scaling far beyond your retargeting pool.

How Lookalike Audiences Work

• Seed Audience: Upload your customer list, pixel data, or engaged users (minimum 100 people, but 1,000+ is better)

• Platform Analysis: Algorithm identifies shared characteristics - demographics, interests, behaviours, online activity

• Audience Creation: Platform finds new people matching those patterns at your chosen similarity level (1% = most similar, 10% = broader reach)

• Targeting: Use lookalike audiences like any other targeting group in your campaign structure

Real-World Example

A meal kit delivery service has exhausted their retargeting pool of 25,000 website visitors:

Manual Interest Targeting Approach:

• Targets: "Healthy eating," "Cooking," "Organic food" → $68 CPA, 1.2% CVR

• Struggles to scale beyond $5K/day spend

1% Lookalike Audience (built from past purchasers):

• Platform identifies patterns: "Health-conscious parents aged 28-45 who engage with time-saving content"

• Result: $41 CPA, 2.1% CVR → 40% lower acquisition cost

• Scales to $25K/day spend profitably

The platform's data revealed their best customers were primarily time-strapped parents (not just health enthusiasts), allowing the brand to find similar prospects at scale. They then optimised creative using A/B testing specifically for this lookalike audience.

Common Mistakes

Learn More

• Cost Per Acquisition (CPA) - How lookalikes impact acquisition costs

• Click-Through Rate (CTR) - Why high CTR without CVR wastes budget

• Creative Testing Framework - Find creative that converts, not just clicks

Quick Takeaway

Lookalike audiences use platform algorithms to find new customers who match your best existing customers - typically delivering 30-50% lower CPA than manual interest targeting when built from high-quality seed audiences.