Open tracking
Measuring email opens by counting requests for a tracking pixel, a method that privacy features and image blocking have made unreliable.
What it means
An open is recorded when a recipient's mail program loads the tracking image, so the count depends on images loading. Apple Mail Privacy Protection prevents senders from learning whether a message was opened, readers whose program blocks images are never counted, and Gmail clipping can cut off a pixel placed at the end of a long message: Mailchimp warns that clipping hides the code that counts opens.
Google states that it does not track open rates, cannot verify open rates reported by third parties, and that low open rates are not necessarily a sign of deliverability or spam problems. Clicks and replies do not depend on images loading.
Related terms
On this site
Sources
What this definition rests on. The wording is ours; the facts are theirs.
- Twilio SendGrid Docs: Tracking settings (open and click tracking)twilio.com
- Apple Support: Use Mail Privacy Protection on iPhonesupport.apple.com
- Mailchimp Help: Gmail is clipping my emailmailchimp.com
- Google, Gmail Help: Email sender guidelinessupport.google.com
All 432 terms in the glossaryThe wiki: blocklists and bounce codes