Email Deliverability FAQ

Emails typically go to spam for several reasons: missing or misconfigured SPF, DKIM, or DMARC records; your domain or IP is on a blacklist; poor sender reputation; spammy content or subject lines; lack of engagement from recipients. Use our free email deliverability checker to diagnose the exact issue with your domain.

SPF (Sender Policy Framework) is a DNS record that specifies which mail servers are authorized to send email on behalf of your domain. Without SPF, spammers can easily forge emails from your domain, and receiving servers may mark your legitimate emails as spam. SPF is essential for email authentication and deliverability.

DKIM (DomainKeys Identified Mail) adds a digital signature to your outgoing emails. This cryptographic signature verifies that the email was actually sent from your domain and hasn't been modified in transit. DKIM requires adding a public key to your DNS records and configuring your mail server to sign outgoing messages.

DMARC (Domain-based Message Authentication, Reporting & Conformance) tells receiving mail servers what to do when SPF or DKIM checks fail. It also provides reports about who is sending email using your domain. Yes, you should absolutely set up DMARC - it protects your brand from email spoofing and phishing attacks.

Use our free email deliverability checker at EmailDiag to scan your domain against 50+ major blacklists including Spamhaus, SpamCop, and Barracuda. If you're listed, we'll show you which blacklists and provide guidance on how to get delisted.

DNS changes typically propagate within 1-48 hours, though most changes are visible within 1-4 hours. The propagation time depends on the TTL (Time To Live) setting of your DNS records and how different DNS servers around the world cache information.

In SPF records, ~all (soft fail) suggests that emails from unauthorized servers should be accepted but marked as suspicious, while -all (hard fail) tells receiving servers to reject emails from unauthorized servers outright. For better security, we recommend using -all once you've confirmed all legitimate sending sources are included in your SPF record.

No, you should only have one SPF record per domain. Having multiple SPF records can cause authentication failures because some mail servers will randomly pick one record, leading to inconsistent results. If you use multiple email services, combine them into a single SPF record using the "include:" mechanism.

SPF has a limit of 10 DNS lookups to prevent denial-of-service attacks. To fix this: 1) Remove unused "include:" statements, 2) Replace "include:" with "ip4:" or "ip6:" where possible, 3) Use SPF flattening services that resolve includes to IP addresses, 4) Consider using subdomains for different email services.

Start with p=none (monitoring mode) to collect reports without affecting email delivery. Monitor the reports for 2-4 weeks to identify all legitimate email sources. Then gradually move to p=quarantine and finally p=reject. This phased approach prevents accidentally blocking legitimate emails.

Use our Email Test feature at EmailDiag. We provide a unique test email address - send an email to it and we'll analyze your SPF, DKIM, and DMARC authentication in real-time, showing you exactly what receiving mail servers see.

Email authentication (SPF, DKIM, DMARC) is crucial for marketing because: 1) It improves inbox placement rates, 2) It builds sender reputation, 3) It protects your brand from spoofing, 4) Major email providers like Gmail and Outlook increasingly require proper authentication, 5) It's required for BIMI (Brand Indicators for Message Identification).