Several metrics can help in measuring the ROI of email marketing campaigns:
Open Rate: The percentage of recipients who open your email. Click-Through Rate (CTR): The percentage of recipients who clicked on one or more links in your email. Conversion Rate: The percentage of recipients who completed the desired action (e.g., making a purchase). Bounce Rate: The percentage of emails that could not be delivered to the recipient's inbox. Unsubscribe Rate: The percentage of recipients who unsubscribed after receiving the email.