How does Facebook know what ads to show me?


People often ask me "how does Facebook know what Ads to show me" It was the second most popular question from my recent email list survey.

How am I being targeted?

As business owners understanding how this works is key to ensuring the success of our advertising efforts inside Facebook and across the wider Facebook audience network.

The ads we see inside Facebook are the result of the kind of audience that an advertiser has selected to use in their campaign.

There are 3 audience types that you can choose to use as an advertiser inside Facebook.

  • A custom audience,
  • A lookalike audience and
  • A saved audience.

What are custom audiences inside Facebook?

A custom audience will be your most powerful and most aligned audience. It is likely to be your cheapest audience. This audience is made up of one of the following options

A Customer file
This is where you upload your email list, your customer database, your LinkedIn connections and Facebook will seek to find this audience on Facebook. It will look to match information about the person with email address being a key matching item within the database. So, whilst you may have 2000 people in your list, Facebook may not be able to exactly match them all of them, so your list is likely to be smaller than the list of contacts.

Website traffic
This is a great way to create an audience. When the Facebook pixel is embedded, you can create an audience from people that have visited any page of your website or a particular page on your website. You can also target people who took specific actions on your website such as how long they spent there, what kinds of actions they took. You can also embed your PIXEL in other third-party apps to track visits, so on landing page software or booking engines. Facebook will store people in this bank of contacts for up to 180 days

App activity
Create a list of people who launched your app or game, or took specific actions. If you connect your Facebook SDK then this is a great way to target a group of people that have completed a series of actions but not others or to showcase new offerings.

Offline activity - This is a new feature
Create a list of people who interacted with your business in-store, by phone or through other offline channels.

Engagement - This has been extensively updated in the last 6 months
Create a list of people who engaged with your content on Facebook or Instagram.
This process is secure and the details about your customers will be kept private. This is a goldmine of value - and why building brand and personal authority prior to your main selling activity is so critical as part of your Facebook Advertising Strategy. That is how you build up your target audience bucket.

This allows you to build an audience and target people who watch your videos. Be careful not to just create an audience of people that watch 3 secs - it’s too short to be valid. Aim for 25 secs for the audience to have any real value for you.

Lead form
This is great because you can target people who not only fill in the form - BUT - target the people who had the intent and opened the form, but then hesitated and didn’t complete it.

Full-screen experience
If you are using the fullscreen experience or collection or CANVAS ads, then this is where you group people who interact with them

Facebook Page
I remember in the bad old days, you couldn’t target your page until you had something like 10000 followers. Now you can target people who don’t even like your page but interact with your content. This is a fantastic feature for advertising and really shows the value of creating interesting content that speaks to your target audience.

Instagram business profile
This option allows you to target people who have checked our Instagram business profile even if they didn’t follow you, as well as allowing you to target people who like your posts, swipe over them, watch videos, share, comment or send you a direct message.

This allows you to target people who have interacted specifically with your events inside Facebook. So any time over the last 180 days, you can touch base with people who may have been interested, but never came. People who have interacted with your events on Facebook. Handy if you run loads of regular events and want to target more of the same kind of people or repeat customers

When we are looking to grow our reach and influence, the next best type of Facebook Audience is a LOOKALIKE audience.

What is a Lookalike audience inside Facebook?

A Lookalike audience is an audience that looks and behaves in a very similar way to your custom audience. When you create a custom audience you are then able to create a lookalike audience from that source group. When you create it, you need to choose the country that you want to focus on and then when you run you ads, you can narrow into a region that suits you. For example, my lookalike audience might be all of Australia, but when I run the ad, I might choose to narrow down to say NSW, or a certain age group. 

This is also a very cost-effective method of finding people as they are potentially very closely aligned with people who behave online in the same way as existing customers, existing fans, existing email subscribers or existing website visitors.

The final group is the SAVED AUDIENCE.

This type of audience is the one that people are most likely to start with. It allows you to target people via 4 key factors. This audience is likely to be the most costly to use in terms of outcomes, but until you build up numbers in your custom audience area, this is where you are going to start.

Demographics: Choose people based on traits such as age, gender, relationship status, education, workplace, job titles and more.

Location: Reach people in areas where you want to do business. Even create a radius around a shop to help boost footfall.

Interests: Find people based on what they're into, such as hobbies, favourite entertainment and more. For business, you might choose pages that they like, business personalities and key influencers in your space, books they might be reading, programs they may purchase or watch.

Behaviours: Reach people based on their purchasing behaviours, device usage and other activities.

Understanding your ideal client persona will be critical to success here as the better you know your audience, the better you will get at finding them inside Facebook.

For example, if your business provides Fitness training then a Facebook ad that targets people in your area interested in Fitness, Diet or Health is likely to perform better than the same ad that just targets everyone in your area.

So how does Facebook ‘know’ that people have been interested in something? Why do I see ads?

It is not just from what you say your interests are in your profile ( although that helps ).

  • It is also how we behave online, what we pay attention to - ie watch or read.
  • What we like and comment on.
  • What we share with our friends.

Advertisers might also choose to target us as a friend of someone who has liked a page. Or they might target us in another way. If you want to know why you are seeing ads, Facebook tells you. This is incredibly useful if you want to understand how your competitors might be targeting people, or why a business you follow is targeting you.

Facebook tells us this.

Yes - it tells us exactly why you are seeing ads. You can see this in the images below.


So if you want to get into the head of your competitors - this is a great way to do that!

How do we know what is performing better? What does Facebook tell us about performance and how do we know it is good?

Stay tuned for my next article on the importance of AB testing, Facebook’s new dynamic ad creative options and when you know you can ramp up your spending.