Understand limitations of open rates

Email open rates used to be a go-to metric for measuring engagement, but that’s no longer the case. Over time, email clients and services have introduced privacy features that either block open tracking entirely or generate false opens, making the data increasingly unreliable.

These changes were led by Apple’s Mail Privacy Protection (MPP), but similar behavior is now seen in other inbox tools and apps too.

See how privacy features affect open tracking

• Apple Mail preloads email content (including tracking pixels by default, often registering an “open” even if the user never actually reads the message.
• Gmail and other clients may block images, including tracking pixels, unless the user enables them manually.
• Many providers now obfuscate or block IP address data, making it difficult to determine where or when an email was opened.
• Depending on the provider or device, open tracking may fail silently or produce misleading results.

The result? Open data does not reflect real user behavior. In some cases, open rates are inflated by automated preloading. In others, they’re underreported due to blocked tracking pixels.

Switch to metrics that matter

Open rates can be tempting to rely on, because they’re one of the first metrics marketers see. But with modern privacy protections affecting tracking accuracy, open rates are no longer a reliable way to measure engagement. To truly understand how your audience interacts with your emails, it’s better to focus on metrics that reflect actual user behavior.

• Shift your focus to metrics that reflect real user interaction, such as:
  • Click-through rates – who’s engaging with your content.
  • Unsubscribe rates – who’s opting out.
  • Bounce rates – how clean your email list is.
• If you’re using personalization or automation, pay attention to contact activity logs to get a fuller picture of what individuals are doing post-send.

While open rates can still hint at deliverability issues or sudden changes in behavior, they should no longer be your primary measure of success.