Modern spam filters analyze multiple factors to evaluate emails:
Sender Reputation: The history of the sender's IP address and domain. Content Analysis: The presence of spammy words, excessive punctuation, or suspicious links. Engagement Metrics: How recipients interact with the emails (open, click, mark as spam). Authentication Protocols: Use of SPF, DKIM, and DMARC to verify sender identity. List Hygiene: Quality and accuracy of the email list being used.