emailrules.today
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DMARC

A DNS policy that tells receivers what to do when SPF/DKIM checks fail for your domain.

Say it out loud

“Our written instruction to Gmail about what to do with mail that fails our checks: ignore it, bin it, or refuse it.”

DMARC ties SPF and DKIM to the visible From domain and states, publicly, what a receiver should do when neither aligns. It can also request aggregate reports so you can see who is sending as you. The policy lives on your domain's DNS, which means no platform can publish it for you and no platform can get it wrong on your behalf.

1
DMARC record per domain
RFC 7489 §6.6.3
DNS recordThe policy, and the three things it can sayPublished valuesscrolls →
Name _dmarc.aurora.com
Value v=DMARC1; p=none; rua=mailto:dmarc@aurora.com;
pct=100; adkim=r; aspf=r
p=none monitor only, deliver as normal

Where every domain starts. It changes nothing about delivery, and tells you everything.

p=quarantine failures go to the spam folder
p=reject failures are refused at the door

The destination. Also the fastest way to break your invoicing tool if you arrive here without reading reports first.

adkim/aspf r = relaxed (subdomains ok), s = strict

Yours

Nobody does this for you.

What goes wrong

Publishing p=reject on day one because a checklist said DMARC was required. Every forgotten sender — the invoicing platform, the recruiting tool, the CEO's newsletter plugin, the ticketing system — starts failing immediately, and you find out from the sales team rather than from a dashboard.

What people get told

The claim. “p=none does nothing, so skip to reject.”

Actually. p=none plus a reporting address is the only way to discover who is currently sending as your domain, and there is always someone you have forgotten. It is the reconnaissance phase, and skipping it is precisely how the rollout to reject goes wrong.

Check it yourself

Read the policy and whether anyone is reading the reports

Run it now →

The dated rules behind this

A definition is not a citation. These are the pages with the primary source, the date it was published, and what to do about it.

See also

Where this sits

Stop 4, identity gets checked. The receiver works out whether the message really comes from who it says it does.

← BeforeAlignmentNext →Email headers

FAQ

Awkward questions

Who is this actually for?

People who ship email and are too busy to re-read every PDF: week-one marketers, lifecycle/CRM, deliverability, multi-country ops, DTC brands, agencies — on Klaviyo, Mailchimp, Braze, HubSpot, SFMC, or something else. Pick your tool and geos so product-specific pages only appear when they match. EU and UK are first-class filters. Not for people who sell tools about email and need a fake score to demo.

Why only ~40 rules? Isn’t that… thin?

On purpose. A wall of 400 undated “best practices” is how you look busy and still get burned. Every page needs a primary source we actually read. Thin and checkable beats fat and folklore. Europe, bulk inbox rules, measurement honesty, and protocol topics like BIMI/DMARC policy are on the shelf when we can cite them — not every Member State and not every vendor myth. Coverage map lists what we still refuse to invent.

Is this legal advice?

No. If it were, you’d have a billable hour and a longer PDF. This is a dated operator reference written by an email geek. Confirm anything high-stakes with counsel who knows your facts. Same for “will this make me compliant?” — no tool does that. Lawyers and judges do. We say what the sources say and what to do first on Monday.

Why no trust score out of 100?

Because we refuse to invent a number you can’t audit. Fake scores sell seed tests and panic. You get findings, dates, and links. If that feels less exciting than a red dial, good — you’re not the red-dial customer.

Why should I trust you more than my ESP’s blog?

ESPs sell seats. Seed-score vendors sell fear. AI invents citations when nobody watches. We sell nothing today — no pixels, no placement scores, no affiliate — so we can say when a tool is the problem. A human verifies, dates, and corrects in public. Tools may help draft; they do not ship unsourced claims. Check the primary links. Fail that test and leave.

Do I need an account?

No. Filters live in this browser and the URL. Share the link. That’s it. Accounts come later only if they earn it — not so we can nurture you about email.

I’m an agency. Where’s multi-client mode?

We tried a client-name CRM on the setup card. It made the product feel like work before it felt useful. Role filters + copy link + one-page brief (optional PDF title) is enough for now. Complexity comes back when the free shelf is habit, not before.

Is the quiet changelog a bug?

No. Quiet means nothing material moved. We don’t invent urgency so the homepage looks “alive.” Sticky risks still show what usually needs a person when the market is still.