Open tracking (and Apple MPP)
Also called: Tracking pixel, Mail Privacy Protection, MPP
Open tracking adds a tiny invisible image to an email; when the image loads, the sender records an “open”.
Apple Mail Privacy Protection (“Protect Mail Activity”) hides the reader’s IP address and downloads remote content privately in the background when a message is received (Apple). The image can load whether or not the person reads the email.
Gmail and Yahoo fetch images through their own proxies, so an open there is real but the location and device are the proxy’s. Corporate security scanners can load images too.
How it affects cold email
Open rates are no longer a dependable measure, and tracking adds HTML and an image to what would otherwise be a plain text email. Replies are the better signal. If you do track, use a custom tracking domain.
How Inboxed handles it
- Open tracking is off by default and can be turned on per campaign. Inboxed counts machine opens (Apple’s prefetching, link scanners) separately from human ones, and labels opens as estimates. If a follow-up depends on opens while tracking is off, Inboxed warns you before launch.
Related terms
Sources
Sources checked on 8 November 2026. Rules change, so check the source before you rely on a detail.
- Use Mail Privacy Protection · Apple, Mail User Guide
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