====== How email opens are tracked ====== Sentori, like all email marketing systems, tracks email opens by embedding a small transparent image inside your email. The image carries a unique ID for each recipient that enables us to log an open for them when it is downloaded. ===== Not all opens can be tracked ===== As a number of email clients do not automatically download images when an email is opened, it is possible that some contacts read your email without us being able to track it. For this reason, email opens are almost always under-reported.