All You Need to Know About Facebook Pixels

Jukka Mäenpää Jan 23 2019 3 PM | 4 min read

Facebook advertisers, have you run into any of the below issues with your campaigns?

  • Optimizing towards a certain event doesn’t work, i.e. when there are no conversions despite placing bids for website events such as purchases

  • Your ads' performance is incorrectly tracked

  • Your retargeting audience isn't populating

If one or a combination of the above is true, continue reading. The culprit could lie in the way your Facebook pixels are set up with your ad sets, ads, audience or catalogs. Read on as we cut through the jargon to help you better understand the relationship between pixels and different objects to debug issues in your Facebook campaigns.  

Pixel events as conversions

When a user takes a specific action on your page, the pixel can trigger an event - standard events correlate to steps in a user’s journey such as “view content”, “add to cart”, “search” or  “purchase” - and sends this information back to Facebook. You can also define custom ones that don’t fit within the standard event definition.

A conversion is defined as an event that we can attribute to a specific source. When an ad tracks a pixel, the events that are triggered can be attributed back to the ad and shown as conversions. Below is an example of an event registering as an ad conversion:

  1. User clicks on an ad to go to a website.

  2. Within one day they perform an action on that website which triggers the pixel to send a Purchase event.

  3. With a “1 day click” attribution window, the Purchase event triggered by the user is attributed as a Purchase conversion to the same ad clicked by the user.

Pixel events and Catalogs

Each item in a product catalog—such as individual product, flight route or hotel has a unique ID. When pixels trigger events on websites where these products, hotels or flights are displayed, the pixel can include the IDs of those products as parameters in the pixel events. The IDs on product pages, which are sent with the pixel, must also match the IDs in the catalog, so that Facebook knows which items a certain user is interacting with. It is considered best practice to use standard IDs like stock keeping unit numbers in both sources.

Event Sources and Targeting Audiences

An event source is a pixel or mobile app that sends signals in the form of events about user activity on your website or application. Since pixel events can be tied back to Facebook users, we can also use the events as a basis for defining our targeted audience. With pixel audiences, we are generally referring to website custom audiences and dynamic audiences:

Website Custom Audiences (WCA): Based on pixel event triggers on your website, which allow you to have audiences for specific events like “users who visited” or more defined audiences like “users who visited and”.

Dynamic Audiences: Used mainly in Dynamic Ads campaigns, they are similar to WCAs but they are ideal when retargeting users who interacted with your catalog items.

Ad Tracking Specification

The ad tracking specification is owned by the ad object. Each ad includes a tracking specification that identifies event sources to consider when looking for events that can be attributed to the ad as conversions. By default, you will be tracking at least the pixel that is being “promoted” by the ad set.

Ad delivery is targeted to users similar to those who have completed the optimization goal action. If you bid for a Purchase conversion event, the Purchase events are gathered from the ad set’s promoted pixel. An ad set must track the promoted pixel through its ads so the conversions are reported to the ad set, and Facebook can optimize towards those conversions. By default your ad would also track engagement on the post used in the ad creative and the page which you are advertising.

Make sure you are tracking the page that you’re sending users from your ads. The tracked pixel should be active on the page.

Learn more about the leveraging the power of pixels for your Facebook advertising and how to set them up in with our comprehensive guide.

   Retail Re-UP: Adjusting to the Next Normal of Social Advertising CHECK IT NOW
Jukka Mäenpää
My time is split between being a Product Marketing Manager at and petting my dog Pippa. I previously worked in customer success and web development, so I love understanding the technical details behind everything that affects our customers.

Read Next