Understanding DMARC: Strengthening Email Security

Email has become an integral part of communication in the digital age, serving as a primary means of professional and personal correspondence. However, the ubiquity of email also makes it a prime target for cyber threats such as phishing and email spoofing. To combat these risks, organizations and individuals turn to technologies like DMARC (Domain-based Message Authentication, Reporting, and Conformance) to enhance email security.

Why are we writing about DMARC today?

Google and Yahoo’s new sender requirements will be coming into force on February 1, 2024. In short, this means that if your company sends email to one of their servers (Gmail and Yahoo) they are going to pay more attention to who is sending the message. They will also check if the receiver can unsubscribe easily.

Gmail DMARC sender requirements
Gmail DMARC sender requirements – Photo by: Photo by Stephen Phillips – Unsplash

My guess is that this is an attempt to combat the increase in SPAM and AI-assisted messages in particular. We know how popular Yahoo and Gmail are with free users. But Google Workspace is one of the most popular email providers for businesses. The other one being Microsoft 365. Speaking of which, Microsoft announced changes to how they are handling DMARC back in July.

It seems, this is definitely something we should be paying attention to.

What is DMARC?

DMARC, short for Domain-based Message Authentication, Reporting, and Conformance, is an email authentication protocol that helps organizations prevent email fraud and protect their email domains from unauthorized use. Introduced in 2012, DMARC is an open standard designed to work alongside existing email authentication mechanisms like SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail).

In practice, this helps with phishing prevention. When an email sender poses as your bank or other provider, asking for sensitive information. It Seems that the email is originating from one location (one email address), when in fact, it’s coming from the attacker. (Email spoofing)

DMARC record checker

How Does DMARC Work?

DMARC builds upon the foundation laid by SPF and DKIM, providing an additional layer of protection against phishing attacks and email spoofing. Here’s a brief overview of how it works:

Authentication Protocols Integration:

whoapi.com MX, SPF, DKIM, DMARC
whoapi.com MX, SPF, DKIM, DMARC
  • SPF (Sender Policy Framework): Verifies the sender’s IP address against a list of authorized sending IP addresses for a domain.
  • DKIM (DomainKeys Identified Mail): Uses cryptographic signatures to verify the authenticity of the sender’s domain.

Policy Setting:

  • DMARC enables domain owners to publish policies instructing email receivers on how to handle emails that fail authentication checks.
  • Policies can be set to “none,” “quarantine,” or “reject.”

Reporting Mechanism:

  • DMARC provides detailed reports to domain owners about email authentication activities.
  • These reports include information about successful and failed authentication attempts, helping organizations monitor and fine-tune their email security settings.

What are the benefits of DMARC:

Photo by Bret Jordan – Unsplash

Phishing Prevention:

  • By enhancing email authentication, DMARC helps prevent phishing attacks that rely on email spoofing to deceive recipients.

Brand Protection:

  • We’ve often mentioned brand protection. Recently we published an article about domain monitoring. DMARC is another way organizations can safeguard their brand reputation by preventing cybercriminals from using their domains to launch fraudulent email campaigns.

Improved Email Deliverability:

Policy Enforcement:

  • Organizations can enforce strict policies on how their emails should be handled, providing better control over their email ecosystem.

Actionable Reporting:

  • DMARC’s reporting mechanism provides valuable insights into email authentication activities, allowing organizations to identify and address potential security issues.

Challenges and Considerations:

  • While DMARC is a powerful tool for enhancing email security, there are challenges and considerations to keep in mind:

Gradual Implementation:

Organizations may need to implement DMARC gradually to avoid disruptions in email delivery, especially if they have not previously used SPF or DKIM. Setting and fine-tuning DMARC policies require careful consideration to avoid false positives or negatives, ensuring legitimate emails are not rejected. Organizations using third-party email services need to coordinate with these providers to ensure seamless DMARC implementation.

In an era where cyber threats are constantly evolving, robust email security measures are essential. DMARC, as part of a comprehensive email authentication strategy, empowers organizations to protect their domains, reduce the risk of phishing attacks, and bolster their overall cybersecurity posture. As businesses and individuals continue to rely on email for communication, the implementation of DMARC stands as a critical step towards a safer and more secure digital environment.

How to Add DMARC at Your DNS Provider

To resolve this error, you must add a DMARC record to your DNS with a fair policy that suits the requirement.

Editing a DNS Zone record with cPanel
Editing a DNS Zone record with cPanel
  1. Visit your DNS provider, or web hosting provider cPanel
  2. Pick the domain to which you want to add the DMARC record and log in.
  3. Click “Add Record.”
  4. Select “TXT” for the record type.
  5. Enter the DNS record. (Example: "v=DMARC1; p=none; pct=100; rua=mailto:email@yourdomain.com")
  6. Save the record.

Policies you can select for the TXT record:

  • none – monitor the email traffic but do not take any actions
  • quarantine – send the unauthorized emails to spam
  • reject – make sure the unauthorized emails don’t get delivered at all


  • Type of record: TXT
  • Name: _dmarc.yourdomain.com
  • Value: “v=DMARC1; p=none; rua=mailto:email@yourdomain.com; ruf=mailto:email@yourdomain.com;”
  • TTL: Default or 14400
whoapi.com example DMARC TXT record
whoapi.com example DMARC TXT record

This article was created with the help of ChatGPT, an AI language model developed by OpenAI.


Goran Duskic has been the Founder and CEO of WhoAPI Inc. since 2011, a company that specializes in developing APIs, including the well-known Whois API. He started his career in internet entrepreneurship in 2006 and has co-founded several online businesses, including a web hosting company that he later sold. Goran's work primarily involves creating practical API solutions to meet technological needs.