Email Deliverability: SPF, DKIM, and DMARC Explained
Why email authentication matters
Without authentication, anyone can send email pretending to be from your domain. ISPs use SPF, DKIM, and DMARC to verify that emails actually come from authorized senders. Without these records, your emails are more likely to land in spam — or be rejected entirely.
SPF: Who can send for your domain
SPF (Sender Policy Framework) is a DNS TXT record that lists the IP addresses and services authorized to send email on behalf of your domain. When a receiving server gets an email from your domain, it checks the SPF record to verify the sender is authorized. Example: v=spf1 include:_spf.aisend.app ~all
DKIM: Proving emails weren't tampered with
DKIM (DomainKeys Identified Mail) adds a cryptographic signature to each email. The receiving server verifies this signature against a public key published in your DNS. This proves the email content wasn't modified in transit and truly came from your domain.
DMARC: Tying it all together
DMARC (Domain-based Message Authentication, Reporting & Conformance) tells receiving servers what to do when SPF or DKIM checks fail: do nothing (p=none), quarantine (p=quarantine), or reject (p=reject). It also specifies where to send authentication reports so you can monitor for abuse.
Setting up with AISend
AISend makes authentication easy. Add your domain in the dashboard, and we show you exactly which DNS records to create. Click Verify to check your configuration. Our AI continuously monitors your domain reputation and alerts you to potential deliverability issues before they affect your inbox placement.
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