Key Aspects
Sender Reputation
Built over time based on sending volume, bounce rates, spam complaints, and authentication compliance.
Authentication Status
Valid SPF, DKIM, and DMARC records significantly improve deliverability.
Content Quality
Clean HTML, appropriate text-to-image ratio, and avoiding spam trigger words all affect inbox placement.
List Hygiene
Sending to valid, engaged recipients reduces bounces and spam complaints.
Factors Affecting Email Deliverability
Email deliverability is a complex interplay of technical and behavioral factors. On the technical side, proper SPF, DKIM, and DMARC configuration is essential. Sending from IP addresses and domains with good reputation, using TLS encryption, and maintaining clean DNS records all contribute to better inbox placement.
Content-related factors also play a significant role. Emails with bloated HTML, excessive images, spam trigger words, or misleading subject lines are more likely to be filtered. Email signatures can affect deliverability if they contain large images, broken links, or poorly coded HTML. Keeping signatures clean and optimized is part of maintaining good deliverability.