Delivery rate refers to the percentage of emails sent that are successfully delivered to recipients' inboxes. It's a key metric for email marketers as it directly impacts the effectiveness of their campaigns.
Factors that impact delivery rate include sender reputation, email content, and email authentication. Subscriber engagement can furthermore influence the delivery rate. A high proportion of inactive email addresses or being marked as spam can also affect delivery.
Think of the delivery rate as the opposite of a bounce rate, which measures the emails that did not arrive. The delivery rate, instead, tells you how affectively email campaigns reach your target audience.