Deliverability
The ability to consistently land in the inbox rather than the spam folder or being rejected.
Deliverability is not the same as delivery. An email can be successfully delivered to a server and still end up in the spam folder — meaning your subscriber will likely never see it. Strong deliverability requires authentication (SPF, DKIM, DMARC), good sender reputation, clean lists, engaging content, and consistent sending patterns.
Related terms
Sender Reputation
A score inbox providers assign to your sending domain and IP based on engagement, complaints, and bounces.
DKIM (DomainKeys Identified Mail)
A cryptographic signature added to outgoing emails that proves the message really came from your domain and was not tampered with.
SPF (Sender Policy Framework)
A DNS record that lists which servers are allowed to send email on behalf of your domain.