Every advertiser eventually faces the same challenge: how to find new audiences that perform as well as their existing customers. Facebook’s Lookalike Audience feature is designed to solve exactly that.

Instead of guessing who might convert, Meta allows you to leverage your own data—such as customers, website visitors, or app users—to automatically find people with similar characteristics. This capability helps advertisers expand reach while maintaining targeting precision, significantly improving campaign efficiency and ROI.

In this guide, we’ll explore how Facebook Lookalike Audiences work, how to create and optimize them, and advanced scaling strategies that align with Meta’s current advertising ecosystem.

What Is a Facebook Lookalike Audience?

A Facebook Lookalike Audience is a targeting feature that helps advertisers reach new users who share traits and behaviors with their best-performing customers. According to Meta, “A lookalike audience uses your existing Custom Audience as a seed to find people who resemble your customers.”

This means Facebook’s algorithm analyzes your seed audience (for example, purchasers or engaged users) and identifies patterns, like demographics, interests, or online behavior—that define those people. It then finds other users across Facebook, Instagram, and the Facebook Audience Network who “look like” your seed audience.

How It Differs from custom audiences and saved audiences

• Custom Audiences are built from first-party data—like customer lists, website visitors, or app users you already know.
  

• Lookalike Audiences expand on that data to find new potential customers similar to your source.
  

• Saved Audiences are manually configured based on demographics, interests, or behavior without any data-driven matching.
  

How Facebook Lookalike Audiences Work

Before creating a Lookalike Audience, it’s crucial to understand what drives Facebook’s matching process. The system relies heavily on machine learning and data signals to find statistically similar users.

The Role of Machine Learning and Meta’s Data Signals

Facebook’s algorithm doesn’t just rely on surface-level interests. It analyzes millions of data points—including user engagement, on-platform behavior, device usage, and ad interactions—to create a predictive model.

According to Meta, the system “uses similarities in behaviors and demographics between your source audience and other users to generate the Lookalike Audience.” In simpler terms, the more accurate and recent your seed data, the smarter the algorithm’s predictions.

Data Sources for Lookalike Audiences

Advertisers can build Lookalike Audiences from multiple data sources, including:

• Customer lists: Emails, phone numbers, or IDs uploaded to Meta Ads Manager.
  

• Website traffic: Captured via the Meta Pixel or Conversions API, which track page visits and conversion actions.
  

• App activity: Events logged through Meta SDK, such as sign-ups or in-app purchases.
  

• Engagement data: Includes Page followers, video viewers, or users who interacted with Instagram content.
  

Each source provides different signal strength. For example, purchase event data usually generates higher-performing Lookalikes than page engagement data.

If you haven’t yet set up Meta Pixel or Conversions API, you may want to review our guide on Facebook Pixel setup and tracking best practices to ensure your data foundation is strong.

How Audience Size and Country Selection Affect Performance

When creating a Lookalike, you’ll choose an audience size between 1% and 10% of the selected country’s population.

• 1% Lookalike: Highest similarity, smallest reach — ideal for conversion-focused campaigns.
  

• 5–10% Lookalike: Broader reach, less precision — better for awareness or scaling.
  

Choosing the correct country or region also matters. Meta’s algorithm finds similar users within that location. Using multiple countries can dilute accuracy and raise CPMs, especially when data sources vary across regions.

Benefits of Using Lookalike Audiences

Once properly configured, Lookalike Audiences become a powerful tool for scalable, data-driven growth. Here are their main advantages:

Scalable Reach with High-Intent Users

Lookalikes help advertisers reach new people most likely to convert—without needing to manually guess demographics or interests. You can instantly scale your campaign to thousands or millions of potential customers with similar characteristics to your best-performing audience.

Improved Conversion Efficiency and CPA

Because these audiences are based on high-quality data, conversion rates tend to outperform traditional interest-based targeting. Advertisers typically see lower CPA (Cost Per Action) and higher ROAS (Return on Ad Spend) compared to broad targeting.

Better Performance Compared to Broad Targeting

While Meta’s Advantage+ audiences offer full automation, Lookalikes provide an extra layer of control and precision. You decide which behaviors to model after—making it ideal for advertisers who want predictability alongside scale.

Simplified Expansion Strategy for Mature Campaigns

Once your campaigns mature and you have strong conversion data, Lookalikes are the easiest way to scale horizontally—expanding to new audiences without rebuilding from scratch.

How to Create a Facebook Lookalike Audience in Facebook Ads

Minimum Requirements for Lookalike Creation

To ensure your Lookalikes are effective, Meta has a few requirements:

• Source Audience Size: Your source audience must contain at least 100 people from a single country. However, for optimal performance, a source audience of 1,000 to 50,000 people is highly recommended. A larger, high-quality source provides the algorithm with more data, leading to a more accurate Lookalike.

• Data Freshness: The data in your source audience should be recent. An audience of customers from the last 60 days will perform better than one from five years ago, as recent behavior is a better predictor of future action.

Creating a Lookalike Audience is a straightforward process within Meta Ads Manager. The most important work happens before you even click "Create Audience."

Step 1: Prepare Your Source Audience (Custom Audience Setup)

This is the most critical step. You first need a high-quality Custom Audience to use as your seed. Navigate to the "Audiences" tab in Ads Manager and create a Custom Audience from one of the sources mentioned earlier (e.g., a customer list, website purchasers, or video viewers).

Refer to this post on how to create an effective Facebook custom audience!

Step 2: Open Meta Ads Manager → Audiences Tab

From your main Ads Manager dashboard, click the "All Tools" (hamburger menu) icon and select "Audiences."

Step 3: Select “Create Lookalike Audience”

Click the blue "Create Audience" button and choose "Lookalike Audience" from the dropdown menu.

Step 4: Choose Your Source Audience

In the "Select your Lookalike source" field, search for and select the Custom Audience you prepared in Step 1.

Step 5: Select Audience Location(s)

Enter the country or countries where you want to find new people. This will be the geographic targeting for your new Lookalike.

Step 6: Choose Audience Size (1%–10%)

Use the slider to select the desired percentage. You can create multiple audiences at once (e.g., 0-1%, 1-2%, 2-5%). Start with 1% for conversion campaigns.

Step 7: Confirm and Create

Click "Create Audience." Meta will begin populating it, which can take anywhere from a few hours to a day. Once it's ready, you can select it during the ad set creation process in your campaigns.

How to Create a Value-Based Lookalike Audience

Value-based Lookalike Audiences take the standard model further by factoring in customer value or lifetime purchase data. This method allows Facebook to prioritize people most similar to your highest-value customers.

Step 1: Prepare a Value-Based Custom Audience

Start by creating a Custom Audience from a customer list that includes a value column.
Your list should contain at least:

• Customer identifiers (email, phone, or Facebook user ID).

• A value field (e.g., revenue, purchase amount, lifetime spend).

Step 2: Create the Lookalike

Next, generate a Lookalike Audience from your new value-based source:

1. In Ads Manager, go to Audiences again.

2. Select Create Audience → Lookalike Audience.

3. Choose your value-based Custom Audience as the source.

4. Select country or region for your Lookalike.

5. Set your audience size (from 1% for highest similarity up to 10% for broader reach).

6. Click Create Audience.

Facebook’s algorithm will now model users who not only resemble your best customers but also have a predicted likelihood of high-value behavior.

Advanced Strategies for Scaling with Lookalike Audiences

Once you’ve mastered the basics, you can layer advanced methods to maximize efficiency and scale.

Using Lookalikes Across Multiple Funnel Stages

Each stage of the marketing funnel requires a different Lookalike size:

• Awareness: Use 10% Lookalike to expand visibility and fill the top funnel.

• Consideration: Target 3–5% Lookalikes to nurture interest and engagement.

• Conversion: Focus on 1% Lookalikes for precision and high intent.

By aligning Lookalike percentage with funnel stage, you maintain both reach and relevance.

Lookalike Expansion Across Countries or Regions

For advertisers targeting multiple markets, consider creating country-specific Lookalikes instead of one global audience. This ensures algorithmic accuracy and compliance with local data norms.

Example: Instead of creating one global audience, build three Lookalikes — US 1%, UK 1%, India 1% — then customize ad messaging per region.

Integrating Lookalikes with Meta Advantage+ Targeting

Meta’s Advantage+ Audiences (formerly “Detailed Targeting Expansion”) now complements Lookalike targeting by expanding delivery beyond your set audience when it predicts better performance.

For advanced advertisers, using Advantage+ in combination with Lookalikes allows Meta’s AI to dynamically test broader audiences while still using your Lookalike as a strong signal base.

How to Measure the Performance of Lookalike Audiences

Creating audiences is easy; proving their value requires diligent measurement. In your Meta Ads Manager, use the "Breakdown" feature to compare performance across different audiences within the same campaign. Pay close attention to these key metrics:

• Cost Per Acquisition (CPA) / Cost Per Result: How much does it cost to get a conversion from this audience?

• Return on Ad Spend (ROAS): For every dollar spent, how much revenue is generated? This is critical for e-commerce.

• Click-Through Rate (CTR): Are users in this audience finding your ads relevant and engaging?

• Conversion Rate (CVR): What percentage of users who click your ad go on to convert?

Always test Lookalikes against your other prospecting audiences (interest-based, broad) to ensure they are delivering superior performance.

Best Practices to Maximize Your Lookalike Audience

To get the best performance from your Lookalike Audiences, it’s essential to focus on the quality of your source data and the relevance of your targeting strategy. A well-structured approach can significantly improve reach, conversion rates, and cost efficiency.

1. Start with a high-quality source audience

The strength of your Lookalike Audience depends heavily on the quality of your seed audience. Use data from customers who have performed high-value actions — for instance, completed purchases, frequent repeat buyers, or long-term subscribers. Avoid including people who only engaged lightly, such as single-page visitors or accidental clicks.

2. Choose the right audience size

Smaller Lookalike percentages (for example, 1%) tend to match users who closely resemble your source audience, giving you higher precision but a narrower reach. Larger percentages (like 5–10%) expand your reach but may include broader characteristics.
Start small to test conversion quality, then gradually scale up once performance stabilizes.

3. Refresh your source data regularly

Your audience data can become outdated over time. Regularly update your source audience, especially for dynamic segments like active purchasers or recent app users, to keep your Lookalike targeting accurate and relevant.

4. Use value-based Lookalike Audiences

If your data includes transaction values or purchase frequency, leverage value-based Lookalike Audiences. Meta’s system prioritizes users with similar value behaviors, helping you reach people who are more likely to make high-value purchases rather than just engage passively.

5. Layer additional targeting options

Combine your Lookalike Audience with location filters, age ranges, or interest-based parameters to refine performance. This prevents wasted ad spend and ensures your creative aligns with the audience’s preferences.

To master these layers and discover all available parameters, explore our complete guide on Facebook ads targeting strategies.

6. Test multiple Lookalikes for different objectives

Create different Lookalike sets from distinct source events (e.g., leads, website visitors, or checkout completions). Comparing their performance helps you identify which customer behavior yields the best ROI for your campaign goals.

FAQs About Facebook Lookalike Audiences

1. How long does it take for a Lookalike Audience to populate?

It typically takes between 6 to 24 hours for a new Lookalike Audience to be fully ready. During this time, its status will show as "Populating." You can still select it for a campaign, but it won't start delivering until it's ready.

2. How often do Facebook Lookalike Audiences update?

Lookalike Audiences automatically refresh every 3-7 days. This means that as your source Custom Audience updates (e.g., with new purchasers), your Lookalike will also dynamically update to reflect those changes, keeping it fresh and relevant.

3. Can I use multiple Lookalike Audiences in one ad set?

Yes, you can stack multiple Lookalikes in a single ad set. This can be useful for consolidating smaller audiences to give the algorithm more room to operate. However, it makes it impossible to know which specific Lookalike is performing best. It's generally better to test them in separate ad sets initially.

4. Should I exclude my Custom Audiences from my Lookalike campaigns?

Yes, it is a best practice. You should exclude your recent purchasers, leads, and website visitors from your Lookalike prospecting campaigns. This prevents you from showing acquisition-focused ads to people who have already converted and ensures your budget is spent on finding genuinely new customers.