After Apple’s iOS 14 update, advertisers began facing new restrictions around data collection, especially from users who declined tracking permissions. In response, Meta introduced Aggregated Event Measurement (AEM).
This protocol allows advertisers to continue measuring conversions while respecting user privacy settings. If you’re running ads on Facebook or Instagram, AEM helps ensure your data remains reliable and compliant with modern privacy standards.
Understanding AEM and configuring it correctly can improve ad performance and attribution.
What Is Meta Aggregated Event Measurement?
Meta Aggregated Event Measurement is a privacy-focused system that supports the measurement of web and app events from people using iOS 14.5 or later. It is designed to keep conversion tracking functional even when users opt out of data sharing through Apple’s AppTrackingTransparency framework.
Each verified domain is limited to 8 prioritized events. Only the highest-ranking event is reported, helping maintain optimization without violating privacy.
AEM applies to both websites and apps, and you can manage it through Meta Events Manager or by using the Meta SDK and tools like the Pomocnik metapikseli for testing event accuracy.
Why Was AEM Introduced After iOS 14?
Apple’s iOS 14 update required apps to ask users for permission before tracking. As many opted out, Meta lost visibility into conversions from iOS devices.
Meta introduced AEM to preserve key signals while respecting user consent.
How Meta AEM Works Behind the Scenes
AEM uses event prioritization to determine which actions to report when a user opts out of tracking. From the eight events configured, only the highest-priority one triggered by the user is sent to Meta.
This allows your campaigns to retain key performance data. For apps, AEM works with Apple’s SKAdNetwork. For websites, it uses the Meta Pixel or Conversions API. Signals from your browser, SDK, or server are processed directly within Meta’s systems. Implementing Server-Side GTM Tracking can enhance data accuracy and reliability.
Setting Up AEM in Meta Events Manager
To start using Aggregated Event Measurement, follow these steps:
- Verify your domain in Meta Business Settings.
- Open Events Manager and select your Pixel.
- Under “Aggregated Event Measurement,” go to Event Configuration.
- Add up to eight conversion events and arrange them in priority order.
Only the events you rank are eligible for tracking when a user opts out. Changes take up to 72 hours and may reset ad learning.
If you’re running app campaigns, AEM setup is handled through the Meta SDK and developer tools.
AEM vs SKAN: What’s the Difference?
Apple’s SKAdNetwork (SKAN) and Meta’s Aggregated Event Measurement (AEM) are both privacy-first tracking solutions but they serve different purposes. Here’s a quick comparison to understand when and where to use each.
Use AEM when running web or app campaigns through Meta. SKAN is mandatory for iOS app installs. I oboje can work in parallel dla better attribution coverage.
Best Practices for Event Ranking and Prioritization
Aggregated Event Measurement allows you to rank up to eight conversion events. The order matters because only the highest-ranking event triggered by a user will be reported if they opt out of tracking.
Common events to include:
- Zakup
- Dodaj do koszyka
- Rozpocznij realizację transakcji
- Prowadzić
- Zakończyć rejestrację
- Wyświetl zawartość
Tips for setting priorities:
- Start with bottom-of-funnel actions like Purchase at the top of the list
- Follow with mid-funnel events like Add to Cart and Checkout
- End with upper-funnel events like View Content
- Avoid frequent changes to preserve campaign learning
- Use custom events only if they reflect measurable business goals
Ranking strategically helps you protect your most valuable signals when data is limited. For additional strategies to optimize your Facebook Ads, explore our Facebook Ads Tips.
Does AEM Still Matter in 2025?
Yes. AEM remains essential for tracking opted-out iOS users. Even with Conversions API, AEM handles event limits and prioritization rules.
Advertisers running mobile-heavy or app campaigns especially benefit from combining both methods.
Końcowe myśli:
AEM remains an important part of Meta Ads tracking. It ensures you can measure key actions, even when full tracking isn’t available. Configure events smartly, pair AEM with Conversions API and use tools for easier setup.
Q. What happens if I don’t set up AEM?
Your ads may deliver, but conversions from opted-out iOS users will be missing or underreported. Campaign optimization will also suffer due to limited data.
Q. Can I track more than 8 events per domain?
No. AEM supports only 8 prioritized events per verified domain. However, you can change or reorder them as needed.
Q. How often can I change my event configuration?
You can edit the event list anytime, but changes may pause ad sets and trigger a 72-hour delay before taking effect.
Q. Is AEM still required if I use Conversions API?
Yes. AEM and CAPI serve different roles. AEM handles event limits and prioritization for opted-out users, while CAPI ensures better data delivery through server-side signals.
Q. Is AEM deprecated or being replaced?
No. AEM remains active as of 2025 and continues to be supported across Meta’s advertising platforms.