How To Use The Facebook Pixel: Custom Audiences and Lookalike Audiences

We covered the step-by-step process to installing the Facebook Pixel in the first blog in this series and last week we detailed how to setup conversion tracking and optimize using the Facebook Pixel.

The final blog in this series will introduce you to Custom Audiences and Lookalike Audiences. These incredibly powerful targeting methods provide you with a number of new ways to engage with potential customers, re-engage with current customers or leads and stretch your targeting to users based on data other than what’s provided by Facebook.

Let’s get started!

What are Custom Audiences?

The Facebook Custom Audience feature allows you to build lists comprised of users based, among other things, on data gathered externally to Facebook’s platform. This can include your own customer lists of email addresses and phone numbers as well as data collected on your website from the Facebook Pixel and data collected from your app.

How to create a Custom Audience

In your Ads Manager select the “Audiences” item from the drop down menu at the top left of the screen. Click the blue “Create Audience” button and select “Custom Audience” from the drop down menu.

From here, you’ll be able to create your Custom Audience in one of four ways:

  1. Customer File: Upload a .csv or .txt file, copy and paste your own customer data into Facebook or sync your email CRM to Facebook. You can match your data fields to the relevant fields on Facebook.
  2. Website Traffic: Create a list of people who have visited your website or specific pages within your website. You can add a timescale to ensure only recent visitors are included.
  3. App Activity: Create a list of people who have carried out specific actions within your app.
  4. Facebook Engagement: Create a list of people who have engaged with one of your videos, lead ads or canvas ads.

A list of all your Custom Audiences will be displayed on the audiences page, along with key stats such as the size of the audience.

When creating your campaigns you’ll have the option to select multiple Custom Audiences to include or exclude from your targeting when you define your ad set audience, budget and schedule.

Custom Audiences can be incredibly powerful when used smartly. For example you can:

  • Retarget customers who have visited your website
  • Retarget customers who have abandoned cart
  • Target your current contacts or leads
  • Target highly engaged customers who have viewed high percentages of your videos
  • Target customers who aren’t opening your emails
  • Exclude current customers from your campaigns
  • Custom Audiences also form the basis of what your Lookalike Audiences will be created from.

What are Lookalike Audiences?

The Facebook Lookalike Audience feature allows you to build lists of potential new customers based off of your existing Custom Audience lists. Facebook analyses the key demographic and targeting features of your Custom Audience and creates a new “Lookalike” Audience, comprised of a small percentage of users in your target region, that match those features.

Therefore you are provided with a new audience list that is similar to your original Custom Audience, but comprised of entirely new targets!

How to create a Lookalike Audience

From the same Ads Manager screen click the blue “Create Audience” button and select “Lookalike Audience” from the drop down menu. From here, you’ll be able to create your Lookalike Audience.

You select the Source of data your Lookalike Audience will be based on from either one of your Custom Audiences or your Facebook Page audience.

The Audience Size is the percentage of the population of the Country you’ll be targeting, which will be the total size of your eventual Lookalike Audience (e.g. The population of USA is 318 million so selecting an Audience Size of 1 will give you a Lookalike Audience of 3.18 million). You can select between 1% and 10% and the smaller the percentage you select the more accurately your Lookalike Audience will match your data source.

As with Custom Audiences, all of your Lookalike Audiences will be displayed in the audiences page, along with data such as the size of the audience. It takes a little while for the Lookalike Audience to be created, so don’t be concerned if your audience size is zero for a few hours.

You’ll be able to include and exclude Lookalike Audiences in the same way as you do Custom Audiences when creating your campaign.


If you’ve read this whole series of posts you now know how to install the Facebook Pixel, setup conversion tracking, and create Custom Audiences, so you understand the importance of the Facebook Pixel.

The Facebook Advertising Platform gives you the ability to advertise to a whopping 1.7 billion people around the globe, but the Facebook Pixel is what really gives you the power to understand how these people are engaging with your brand once they leave Facebook.

Thanks for reading and please share the knowledge!