DMARC Validator
RFC 9989 compliantValidate and Refine Your Policy
Our DMARC validator checks your record against RFC 9989 for correct syntax, valid tag combinations, and policy configuration issues. It flags misconfigurations that affect both enforcement and reporting, so you can be confident your DMARC setup is working as intended.
What is DMARC?
DMARC (Domain-based Message Authentication, Reporting, and Conformance) is an email authentication protocol that builds on SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) to prevent email spoofing and phishing. DMARC provides domain owners with visibility into how their domain is used across email channels and enforces a policy to handle unauthenticated messages (e.g., reject, quarantine, or allow).
Why is DMARC Important?
- Protection Against Spoofing and Phishing: DMARC helps protect your domain from being used in fraudulent emails.
- Improved Deliverability: Authenticated emails are more likely to land in inboxes, increasing engagement and trust.
- Visibility into Email Ecosystem: DMARC generates reports that provide insights into how your domain is used by legitimate and unauthorized senders.
- Enforcement of Authentication Policies: It ensures messages that fail SPF and DKIM authentication are handled according to your policy (e.g., rejected or quarantined).
How Does DMARC Work?
- Policy Definition: Domain owners publish a DMARC record in their DNS specifying the policy for handling unauthenticated emails (none, quarantine, or reject).
- Alignment Checks: DMARC checks if the "From" header aligns with SPF and/or DKIM to verify authenticity.
- Reporting Mechanism: DMARC generates two types of reports:
- Aggregate Reports: Summarized data on authentication results.
- Failure Reports: Detailed information about specific authentication failures.
Common DMARC Issues
- Incorrect Syntax: Errors in the DMARC DNS record format can cause validation failures.
- Policy Misalignment: Failing to align SPF, DKIM, and the "From" domain can lead to unauthenticated messages.
- Overly Permissive Policies: A "none" policy provides insights but doesn't prevent spoofing.
- Improper Reporting Configuration: Missing or incorrect email addresses for receiving DMARC reports.
Best Practices for DMARC
- Start with a "none" policy to gather data before moving to enforcement.
- Regularly review and analyze DMARC reports to identify unauthorized usage.
- Align your SPF and DKIM records with the "From" domain.
- Gradually enforce stricter policies ("quarantine" or "reject") as alignment improves.
- Monitor changes in email authentication regularly to maintain security.
Best Practices for DMARC
The internet is evolving, and so are email security best practices. Read the current best practices for your DMARC setup.
New to DMARC?
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DMARC reports explained
DMARC reports are a powerful tool for detecting issues with your DKIM and SPF setup. Let me guide you through the most common DMARC report types and dive into the details of some of ours to help you better understand your own.
The URIports
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LearnDMARC.com
Get a visual breakdown of how email servers communicate, giving you a better understanding of SPF, DKIM, and DMARC and how they work together.
Go to LearnDMARC.com