ISPs and email clients use various metrics to assess sender reputation. These include:
Bounce Rates: The percentage of emails that cannot be delivered. Complaint Rates: The number of recipients marking your email as spam. Engagement Rates: How recipients interact with your emails, such as open rates and click-through rates. Sending Volume: Consistency in the number of emails sent over time. Spam Trap Hits: Sending emails to addresses specifically set up to identify spammers.