Why (not) to use Facebook interests & lookalikes

As you may already know, advertising on Facebook is different than advertising on other platforms. Unlike other advertising channels, Facebook doesn’t offer keyword targeting. Instead, Facebook lets you target people based on their interests. The reason for this is that people don’t come to Facebook to search, they browse for entertainment. On Google, you can target someone who searches for specific terms, whereas on Facebook, you would be able to target someone who has a particular interest. 

The main problem with targeting people based on interests is that these interests tend to be inaccurate or too broad to be effective for segmentation. Interests are determined based on a user’s activity on Facebook, the pages they visited, and data that Facebook gets from third parties. 

You can view your own ad preferences here to see your associated interests:

https://www.facebook.com/adpreferences/ad_settings/?entry_product=settings_ads_page_redirection

Here is an example of how it looks – 

About a year ago we had a conference call with a few developers from Facebook. We were trying to improve our understanding of how the targeting algorithm works to better structure our campaigns. The first question that one of them asked me was, “Why are you using interests in your ads?” My answer was that we thought that interests are offered to help us narrow down our audience. He then replied that they have no evidence that shows that interests work in that way. Crazy!

BUT TO REALLY UNDERSTAND WHY INTERESTS DON’T WORK, YOU NEED TO UNDERSTAND THE FUNDAMENTALS OF TARGETING OPTIMIZATION.

It’s much simpler than you probably think. When you create a campaign and selected your objective, you are telling Facebook exactly what you want to achieve. Facebook will start slowly delivering your ads to people who are likely to be interested. Even if your campaigns have zero conversions, Facebook will use other signals to better match your ads to the relevant people. If you don’t have any conversions, they will use intro signals, which are metrics like relevance rate, engagement rate, and others to better understand the relevance of your ads. 

Once they reach the relevant audience and start to get you conversions, they will analyze the characteristics and behaviors of the users who converted to find similar users. From there, the more conversions the campaign has, the better the performance.

You are probably wondering what interests have to do with all this? When creating an ad without using interests, you are giving Facebook’s built-in targeting algorithm complete freedom to target the audience they think is relevant. If you would use an interest, you would limit the audience the ad can target. 

Imagine having a pool of 100 people. The targeting algorithm can deliver more effectively if you give it the flexibility to decide how to target that audience. With a very low amount of exposure, Facebook’s data sampling can precisely target your audience. 

Now if instead, you’d target by interest, you would automatically segment your audience to a smaller number of people, and that can create negative results. For example, if you select people who are interested in some broad interest like sports, it would limit your audience to only people who have been labeled as interested in sports, which is probably inaccurate. 

Regardless of how inaccurate the interests might be, by narrowing down the audience size you are limiting your ads to less cost-effective opportunities. Think about it – if you give the system more options to choose from, it can change delivery based on the best opportunities at a given moment. It can target a specific group when the prices are less competitive, or another part when there is more demand in that area. The more freedom you give to the targeting algorithm, the more effective the results.

WHEN CAN YOU USE INTERESTS?

If you’d still like to use interests despite the evidence against them, here is what I would suggest.

When you start targeting with no data history on your pixel or your website, you can “help” the system by narrowing down your audience by using “relevant interests.” 

Then, when you have 50 conversions a week across your account, start moving away from using interests for new campaigns. The more conversions you have, the more using interests will get in the way of your results. 

If you have 50 conversions per week, that’s around 200 conversions per month. Facebook saves pixel data for 180 days (at least that’s what they claim publicly). Imagine how much data Facebook already has about your audience before you launch your campaign. If you have many conversions and you are still not getting good results, targeting is not the issue. 

IN SUMMARY: 

When it comes to setting targets in your advertising campaigns, interests are different than keywords. Keywords are used to target what people are searching for, while interests are used to target what they might be interested in. Interests on Facebook are generally inaccurate and there hasn’t been any proof to date that they actually work. When you give it the chance, Facebook optimizes your targeting based on your pixel and campaign data. The more data, the better the performance. Interests will only get in the way of better performance. Should you choose to use them, only use them when your campaigns have little to no data and move away from using them once your campaigns mature. My recommendation is to give Facebook complete targeting freedom from day one and focus more on your creatives and product and less on your targeting.