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DMARC Record Generator — enforce, don't just publish.
SPF and DKIM are published, and someone is still sending as your domain. DMARC is the record that tells Gmail, Outlook and Yahoo exactly what to do when a message fails both. Build one with a real rollout plan, not just p=none forever.
- No account needed
- Safe none → quarantine → reject rollout built in
- Compares against your live DNS
Applies the policy to only this share of failing mail. Leave at 100% unless you're gradually rolling out enforcement.
Relaxed (default) allows subdomain matches, e.g. mail.yourdomain.com aligns with yourdomain.com. Strict requires an exact match.
v=DMARC1; p=none - Go to your DNS provider
- Add a TXT record at host
_dmarc(e.g._dmarc.yourdomain.com) - Paste the record above as the value
- Start at
p=none, read your aggregate reports for 1-2 weeks, then move toquarantineand finallyreject
How this works
DMARC, in plain English.
What is DMARC actually for?
SPF and DKIM each verify one thing, but neither tells a mailbox provider what to do when a check fails, or whether the "From" address a human sees actually matches what was verified. DMARC adds that missing policy layer, plus a reporting channel so you can see who is sending mail as your domain — including attackers.
Why start with p=none?
p=none takes no enforcement action — it only turns on reporting. That lets you see, via aggregate reports, every legitimate source currently sending as your domain before you risk blocking any of it. Jumping straight to reject is how real marketing or support tool mail gets silently dropped.
What are aggregate reports (rua)?
Daily XML summaries most major mailbox providers send to your rua address, listing every sending source seen, and whether it passed SPF/DKIM alignment. Most teams pipe these into a parser or a tool like Brain rather than reading raw XML by hand.
Does DMARC alignment work differently from a plain SPF/DKIM pass?
Yes — alignment additionally requires the domain in SPF or DKIM to match the visible From address (exactly, in strict mode; or same organizational domain, in relaxed mode). A message can pass SPF and DKIM individually and still fail DMARC if neither one aligns with the From header.
Shortlisting tools?
See what a real diagnosis looks like.
Three causes hid behind one Gmail crisis. Read the full walkthrough, then run the same audit on your own domain.
