DMARC stands for Domain-based Message Authentication, Reporting & Conformance.
It’s an email security standard that helps stop spam, phishing, and email spoofing—basically, it keeps bad actors from pretending to send email from your domain.
Here’s the plain-English version:
What problem DMARC solves
Without DMARC, anyone can forge the “From” address in an email and make it look like it came from your company or domain. That’s how a lot of phishing attacks work.
DMARC tells receiving mail servers:
- How to check if an email is legit
- What to do if it’s not
- How to report back what they’re seeing
How it works (the trio)
DMARC sits on top of two other email checks:
- SPF – verifies the sending server is allowed to send mail for your domain
- DKIM – verifies the message wasn’t altered and is cryptographically signed
DMARC says:
“If SPF or DKIM passes and aligns with my domain, accept the email. If not, follow my rules.”
DMARC policies
You publish a DMARC record in DNS that tells servers what to do with failing emails:
p=none→ monitor only (no blocking, just reports)p=quarantine→ send suspicious mail to spamp=reject→ block it completely 🚫
Reporting (the underrated superpower)
DMARC sends you reports showing:
- Who is sending email using your domain
- Which emails pass or fail authentication
- Where phishing attempts are coming from
This is huge for visibility and cleanup.
Why DMARC matters
- Protects your brand and customers
- Improves email deliverability
- Required by many providers (Google, Yahoo, etc.) for bulk senders
- Reduces phishing and spoofing dramatically
TL;DR
DMARC is your domain saying:
“Here’s how to verify my emails, here’s what to do with fakes, and please tell me what you see.”