Glossary
Email Deliverability — What It Is and How to Improve It
Email deliverability is the ability of an email to reach the recipient's inbox rather than their spam folder or being rejected entirely. It is determined by a combination of sender reputation, authentication records (SPF, DKIM, DMARC), IP reputation, content quality, and recipient engagement. High deliverability means your legitimate emails consistently reach inboxes.
What Affects Email Deliverability
- Sender authentication: SPF, DKIM, DMARC
- IP reputation: is your sending IP on blocklists
- Domain reputation: how long you've been sending, bounce rates, spam complaints
- Content: spam trigger words, HTML/text ratio
- Engagement: open rates, click rates, unsubscribes
How to Check Your Deliverability
Run DNS Preflight with your sending IP and domain — it checks authentication records, IP reputation, and blocklist status in one pass.
Run a full check on domainpreflight.dev
Open DNS Preflight →FAQ
What is email deliverability?
Email deliverability is the rate at which your emails successfully reach the inbox rather than spam folders or being rejected. It depends on authentication, reputation, and content.
What is the difference between delivery and deliverability?
Delivery means the email was accepted by the receiving server. Deliverability means it reached the inbox. An email can be delivered (not bounced) but still go to spam.
How do I improve email deliverability?
Set up SPF, DKIM, and DMARC correctly, ensure your sending IP has a PTR record, keep bounce rates under 2%, and warm up new IPs gradually.