How is the open rate counted?

An open rate is counted when the open pixel, that is inserted invisibly at the top or bottom of the email, is downloaded. When the recipient opens only the sent email but does not click show images, the open rate for the contact is not counted since the open pixel was not triggered.

When the recipient clicks a tracked link in the email, it is an implied open and is counted. If you see a contact within reporting who has a click and open event with an identical time stamp, this can mean Acoustic Campaign created the open event due to the first click. A click is how Acoustic Campaign tracks opens on a text version of the email, since HTML is not included within a text version (meaning it cannot insert a transparent open pixel).