Learn how to use Facebook targeting with Core Audiences, Custom Audiences, and Lookalike Audiences. Includes 2025 best practices for broad targeting, retargeting segments, ideal audience sizes, and tips to scale conversion campaigns efficiently.
Targeting is the difference between Facebook ads that work and money that gets burned. If you talk to the wrong audience—no matter how good the creative is—you won’t get results. If you reach the right audience with the right message, you can achieve CPCs and CPAs other channels can’t even come close to.
Core Audiences: Facebook’s own data—age, gender, location, interests, behavior. Good for new campaigns without first-party data.
Custom Audiences: Your own data—website visitors, customer lists, app users, video viewers, social-media interactions.
Lookalike Audiences: Users similar to your Custom Audience. Often the best-performing option for conversion campaigns.
Core Audiences are based on the data Facebook has collected about its users. The key targeting options:
Demographics: Age, gender, relationship status, education level, job field. The foundation of any audience.
Geography: Country, region, city, ZIP code, or even a radius around a specific location. Especially relevant for local businesses.
Interests: Topics, pages, and activities users are interested in. Caution: interest targeting is becoming less accurate because Facebook gets less browser data.
Behaviors: Purchase behavior, device usage, travel behavior. Often underestimated, but very valuable for specific audiences.
Trend 2025: Broad targeting (minimal targeting, Facebook optimizes on its own) works better for many campaigns than narrow interest targeting—because with enough conversion data, Facebook’s algorithm becomes very precise.
Website Custom Audiences (via Pixel)
Reach website visitors from the last 30, 60, 90, or 180 days. Segment by pages visited (e.g., pricing page = hot leads), time spent on site, or events taken (AddToCart without Purchase = classic retargeting audience).
Customer lists (Customer Lists)
Upload your CRM data (email addresses, phone numbers) and reach existing customers directly on Facebook. Important for: retention campaigns, cross-selling, excluding existing customers from acquisition campaigns.
GDPR note: Uploading customer data as a Custom Audience requires a lawful basis (e.g., consent or legitimate interest). Meta hashes the data before transmission, but legal compliance is the company’s responsibility.
Engagement Custom Audiences
Users who have interacted with your Facebook or Instagram content: video viewers (by percentage watched), people who visited or liked your page, people who engaged with your posts, lead form users.
Lookalike Audiences are the most powerful method for finding new, purchase-ready audiences. Facebook analyzes your Custom Audience and finds users with a similar profile and behavior.
The percentage setting (1% to 10%) determines similarity: 1% = most similar, smallest group, highest quality. 5% = broader group, good for scaling. 10% = very large, lowest similarity, cheapest CPM.
Best sources for Lookalike Audiences: customers who purchased (Purchase Custom Audience)—the most valuable source. High-quality leads. Top 25% of website visitors by time on site. Value-based Lookalike (based on customer value in your CRM).
Too small (under 50,000): Facebook has too little room to optimize, frequency rises quickly.
Ideal (100,000–2,000,000): Enough reach for optimization without targeting too broadly.
Too large (over 10 million): Loses precision, wasted impressions increase.
Successful Facebook targeting isn’t a one-time setup—it’s an ongoing process: build Custom Audiences, test Lookalikes, evaluate broad targeting, analyze results, and iterate. The audience that works best today might not be the best one tomorrow.