Abstract: An email campaign is analyzed by sending an email message including a tracking code that requests content from an initial-engagement location (e.g., a server). The tracking code requests the content from the initial-engagement location when the email message is opened by a mail user agent operated by a recipient. Requests sent to the initial-engagement location are then tracked to measure the number of recipients that open the email message. A first redirect response is then served from the initial-engagement location to the mail user agent of the recipient after a first delay period to cause the mail user agent of the recipient to then request content from a first redirect location; and requests sent to the first redirect location are tracked to measure the number of recipients that keep the email message open in the mail user agent for through all of the first delay period.

Abstract: An email campaign is analyzed by sending an email message including a tracking code that requests content from an initial-engagement location (e.g., a server). The tracking code requests the content from the initial-engagement location when the email message is opened by a mail user agent operated by a recipient. Requests sent to the initial-engagement location are then tracked to measure the number of recipients that open the email message. A first redirect response is then served from the initial-engagement location to the mail user agent of the recipient after a first delay period to cause the mail user agent of the recipient to then request content from a first redirect location; and requests sent to the first redirect location are tracked to measure the number of recipients that keep the email message open in the mail user agent for through all of the first delay period.