Validation

What is validation in email?

Validation in email authentication refers to the process of verifying that a message, sender, or domain meets established trust and security requirements. It ensures that an email was sent by an authorized source, has not been altered in transit, and aligns with published domain policies. Validation forms the basis of technologies like SPF, DKIM, and DMARC, which protect domains from spoofing and phishing.

Every time an email is received, the mail server performs multiple validation checks. These confirm that the sender’s identity is legitimate and that the message complies with the authentication data stored in DNS. The results of these checks determine whether the email is delivered, quarantined, or rejected.

How Validation Works in Email Systems

Email validation relies on both DNS records and message headers to verify authenticity. The most common mechanisms include:

• SPF (Sender Policy Framework): Confirms that the sending IP address is authorized by the domain’s SPF record.
• DKIM (DomainKeys Identified Mail): Validates the message’s digital signature using a public key published in DNS.
• DMARC (Domain-based Message Authentication, Reporting, and Conformance): Aligns SPF and DKIM results with the visible From domain and applies a policy for handling failures.

Beyond authentication, validation also occurs in message transport and content analysis. SMTP servers validate DNS lookups, reverse DNS records, and HELO hostnames, while filtering systems validate links and attachments to detect malware or phishing attempts.

Types of Validation in Email Communication

Validation spans several technical layers that work together to ensure secure and consistent message delivery:

• DNS Validation: Checks the presence and correctness of DNS records such as SPF, DKIM, and DMARC.
• Header Validation: Ensures email headers like From, Return-Path, and Authentication-Results are properly formatted and aligned.
• Policy Validation: Applies DMARC policies (none, quarantine, or reject) to determine message handling outcomes.
• Content Validation: Scans message content and links for spam or malicious patterns before delivery.

Each validation layer contributes to building a trusted identity framework across the email ecosystem, allowing providers to prioritize verified senders and penalize those who fail authentication.

Validation and DMARCeye

DMARCeye continuously validates the integrity of your domain’s email authentication setup. By checking SPF, DKIM, and DMARC records across your DNS configuration, DMARCeye detects missing or incorrect entries that could lead to message rejection or spoofing vulnerabilities.

The platform also validates authentication results from live message traffic, ensuring that every legitimate sender aligns with your domain policy. With detailed reporting and guided recommendations, DMARCeye simplifies validation management, helping organizations maintain trust and deliverability at scale.

Sign up for a free trial of DMARCeye today and secure your email domain.

To learn more about DMARC and DMARC-related terms, explore the DMARCeye Glossary.