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Is your domain protected from
email spoofing?

Enter your domain and we'll check your DMARC, SPF, and DKIM records — then explain what they mean in plain English.

We only look up public DNS records. We don't store your domain or send you spam.

DMARC SPF DKIM
Plain English. No jargon.
THE BASICS

How email authentication works

DMARC doesn't work alone. It builds on SPF and DKIM to tell inbox providers what to do when something looks wrong.

1

SPF — who's allowed to send

SPF is a list in your DNS of mail servers permitted to send email for your domain. If someone sends from a server not on that list, receivers may flag or reject it.

Think of it as a guest list for your domain's outbound mail.

2

DKIM — proof it wasn't tampered with

DKIM adds a digital signature to outgoing mail. Receiving servers verify it against a public key in your DNS — confirming the message wasn't altered in transit.

Like a wax seal on a letter.

3

DMARC — what to do when checks fail

DMARC tells inbox providers what to do with mail that fails SPF or DKIM: monitor (none), quarantine, or reject. It also tells them where to send reports about who's sending as you.

The policy layer that ties everything together.

Why this matters now: Anyone can try to send email pretending to be your company. Google and Yahoo require proper email authentication for bulk senders. Even if you're not a bulk sender, spoofed email from your domain can damage your reputation and land your real mail in spam.

Who's sending email on your behalf?

Most businesses have more senders than they realize. Every service that sends as your domain needs to be in your SPF record and signing with DKIM.

Common authorized senders
  • Microsoft 365 / Google Workspace (day-to-day email)
  • Mailchimp, HubSpot, Constant Contact (marketing)
  • SendGrid, Mailgun, Amazon SES (transactional)
  • Zendesk, Freshdesk, Shopify (notifications)
Signs something's wrong
  • Legitimate mail landing in recipients' spam
  • Customers reporting phishing from your domain
  • DMARC reports showing unknown senders
  • No DMARC record at all
NEED A HAND?

Email authentication is tricky. We make it simple.

Setting up DMARC, SPF, and DKIM across Microsoft 365, Google Workspace, and your marketing tools takes time and DNS know-how. Network26 handles it for businesses across Washington — usually in a single session.