Facebook displays an event match quality score once server-side tracking has been implemented. The rating – indicated as a score out of 10 – indicates how effective the customer information sent from the advertiser’s server may be at matching event instances to a Facebook user account.
High-quality event matching improves ad attribution and performance.
When setting up Conversions API, advertisers can trigger a server-side event, which simply sends a signal back to Facebook’s server that a conversion event has occurred, which helps ensure all events are captured in Events Manager, irrespective of cookie and tracking restrictions. However, this information alone is not enough for Facebook to match the event to an ad click or a user account.
If the event includes customer information, only then can Facebook match the event to a specific user’s actions.
Why is Facebook event match quality important?
Event match quality is used to assess whether you’re sending the right customer information to match your events to a Facebook account. Customer information parameters help Facebook match your events to a Facebook user account so they can attribute conversions to clicks on your ads.
The event match quality score indicates whether you have set up your customer information parameters correctly. The higher the score is, the better. A perfect score (10/10) is only awarded to CAPI implementations that send almost all available parameters for nearly 100% of server events.
While this may seem like a Facebook tracking problem, it is actually very important for advertiser for two reasons:
- Performance measurement
Have you seen a significant drop-off in Facebook ad performance since May 2021? If yes, this is most likely due to the effect of iOS 14.5, which rolled out on 26 April 2021. The effectiveness of your ad campaigns may be significantly under-valued if a number of conversions aren’t reported correctly and attributed back to Facebook ads. We’ve seen as much as 50% of conversion loss for clients whose customer base was largely iOS users. - Ad delivery
In addition to the strategic and reporting challenges created for advertisers by under-reported conversion numbers, the Facebook algorithm itself relies on this data when optimising ad delivery and audience selection. If none of your clicks seem to convert, Facebook may show sub-optimal ad variations, switch away from higher-performing audiences if they reportedly don’t seem to be converting, and eventually Facebook may throttle ad delivery altogether.
How is match quality calculated?
Facebook calculates the score by looking at which customer information parameters are received from your server, the quality of the information received and the percentage of event instances that are matched to a Facebook account.
Event match quality is calculated daily.
What is a good match quality score?
Upper-funnel events, such as PageView, ViewContent, AddToCart, and even InitiateCheckout may not include much customer information, as visitors may not be required to login or sign up for an account when they trigger these events. Quality scores for such events on Facebook often tend to be between 3/10 and 5/10.
Deeper-funnel events, such as AddPaymentInfo, Purchase, Lead, and CompleteRegistration should include much more customer information, since visitors would typically have shared at least some personal details to get to that stage.
For conversion events you should aim for a score of 6+
How can you improve Facebook event match quality?
The main customer information parameters that Facebook uses for matching, in approximate order of importance are:
- Facebook login ID
- Mobile number
- IP address & user agent
- fbp (browser ID)
- fbc (click ID)
- First name
- Last name
The IP address & user agent are required for all web events. Facebook cookie values – fbp and fbc – should also be detected where present and sent with every server event. If your score for upper-funnel events is below 4/10, you should at the very least ensure you include these four parameters.
If your score for deeper-funnel events is below 6/10 you need to include at least the four most common parameters mentioned above, and also send email addresses and/or phone numbers, along with the provided first & last names. Email addresses and mobile numbers are almost always available to Facebook, and are unique to a user, which makes them the most important fields for matching.
Other data you can include to improve matching accuracy include:
- Date of birth
- Gender
- Address (city, state, postcode, country code)
- Subscription ID
- External ID
User privacy considerations
When deciding whether to share your customer information with Facebook, ensure you keep their privacy in mind. You should only share information that customers have explicitly consented to sharing, and which is clearly outlined in your privacy and cookie policy.
Any personally identifiable information and contact information, such as customer names, email addresses, dates of birth and home addresses must be hashed using SHA256 encryption before it is send to Facebook’s CAPI server.
Google and Apple are changing the landscape for Facebook advertising, with new features that empower users to control how their private information is used. While these changes make it more challenging than ever to measure marketing performance on Facebook and Google, implementing server tracking technology correctly will allow you to stay ahead of the competition.
