DMARC
DMARC (Domain-based Message Authentication, Reporting & Conformance) is an email standard that tells receiving mail servers what to do with messages that fail SPF or DKIM checks — and sends you reports. It prevents spoofing of your domain and is now effectively required by Gmail and Yahoo for bulk senders.
How it works
You publish a DMARC policy as a DNS TXT record. It sets a policy (none / quarantine / reject) for unauthenticated mail claiming to be from your domain, and an address to receive aggregate reports.
Why it matters
Without DMARC, anyone can spoof your domain, and major providers may throttle or reject your legitimate bulk mail. A 'reject' or 'quarantine' policy protects your brand and your deliverability.
How Autocloz handles it
Autocloz monitors SPF, DKIM and DMARC for every connected sending domain and flags misconfigurations before they tank a campaign.
FAQ
Is DMARC required?
Since 2024, Gmail and Yahoo require SPF, DKIM and a DMARC policy for bulk senders. Even below bulk thresholds, DMARC materially improves deliverability and blocks spoofing.
What DMARC policy should I use?
Start at p=none to collect reports, confirm your legitimate mail passes SPF/DKIM aligned, then move to quarantine and finally reject.
Related terms
Cold email deliverability is the share of your outbound cold emails that actually reach the recipient's inbox (not spam, not blocked). It depends on domain authentication (SPF, DKIM, DMARC), sender reputation, mailbox warmup, list hygiene and content — not just whether the email was 'sent'.
SPF (Sender Policy Framework) is an email-authentication standard that lets a domain owner publish, in DNS, the list of mail servers allowed to send email on the domain's behalf. Receiving servers check the sending IP against that list to help detect spoofing and decide whether to trust the message.
DKIM (DomainKeys Identified Mail) is an email-authentication method that attaches a cryptographic signature to each message. The receiving server verifies the signature against a public key in the sender's DNS, proving the message wasn't altered in transit and genuinely came from the signing domain.
Mailbox warmup is the practice of gradually increasing a new email account's sending volume while generating positive engagement (opens, replies, moving mail out of spam) so mailbox providers build trust in the sender before real campaigns ramp up.