What is a DMARC record?

A DNS TXT record on _dmarc.domain that sets a policy (none, quarantine, or reject) for mail that fails SPF or DKIM alignment, and names a report mailbox.

How do I create a DMARC record?

Choose a policy, add at least one rua address, and publish one TXT on _dmarc.yourdomain. This generator writes that string.

What should my DMARC policy be?

Start with p=none so you only monitor. Move to quarantine, then reject, after reports show legitimate mail passing.

How do SPF and DMARC work together?

SPF lists senders. DMARC requires the SPF domain (or DKIM domain) to align with the visible From domain, then applies your policy on failure.

How do I start with DMARC monitoring?

Publish p=none with a rua mailbox you read. Do not skip monitoring and jump to reject on a domain that still has unknown senders.

What is DMARC Record Generator?

A free online builder for a DMARC TXT record aimed at Microsoft 365 and small-business email administrators.

How does the DMARC Record Generator work?

It assembles v=DMARC1 tags from the policy, report addresses, percentage, and alignment you choose.

How do I use the DMARC Record Generator?

Enter the domain and rua address, pick a policy, and copy the TXT onto _dmarc.

Is this DMARC Record Generator free to use?

Yes. It is free with no sign-up.

Can I use the DMARC Record Generator on mobile?

Yes. Mobile browsers are supported.

All free tools

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Microsoft 365

DMARC Record Generator

Create a DMARC TXT record for _dmarc, start with monitoring, and tighten policy once SPF and DKIM pass on Microsoft 365.

Runs in your browser — your data stays on your device

Free tool

Domain

Percentage (pct)

Aggregate reports (rua)

Forensic reports (ruf, optional)

Policy (p)

Subdomain policy (sp)

Alignment

Host / name: _dmarc.contoso.com
Type: TXT

TXT value

v=DMARC1; p=none; rua=mailto:dmarc-reports@contoso.com; adkim=r; aspf=r

Create a TXT record on _dmarc.contoso.com.
Paste this value: v=DMARC1; p=none; rua=mailto:dmarc-reports@contoso.com; adkim=r; aspf=r
Confirm SPF exists on the apex and that you have only one DMARC record.
Watch rua reports before you tighten p=none to quarantine or reject.
p=none only monitors. Read aggregate reports for two to four weeks, then move to quarantine and reject.
DMARC needs a working SPF record and, for full pass, DKIM. Generate SPF first, then publish this TXT on _dmarc.

DMARC tells receivers what to do when SPF or DKIM fail alignment. The safe start we teach every Microsoft 365 tenant is p=none plus a mailbox that actually reads aggregate reports. Jumping straight to p=reject without watching rua is how small businesses quarantine their own invoices. This free DMARC record generator builds the TXT for _dmarc.yourdomain, sets rua, and keeps relaxed alignment until you know every sender. Use it with the SPF generator and Exchange Online.

How to use the DMARC Record Generator

1
Enter the domain and an email address that will receive aggregate (rua) reports.
2
Start with policy none. Keep relaxed DKIM and SPF alignment unless you already enforce strict alignment.
3
Copy the TXT value onto _dmarc.yourdomain, then move to quarantine and reject after you read two to four weeks of reports.

Why SPF and DMARC belong together

SPF authorises senders. DKIM signs messages. DMARC sets policy when those checks fail. A domain with SPF and no DMARC still lets receivers accept spoofed mail. A domain with DMARC reject and a missing marketing include starts losing real mail. Email administrators publish SPF first, add DMARC at p=none, then tighten. That sequence is still the one we use on production Microsoft 365 tenants.

DMARC record generator with examples

For contoso.com with p=none and rua dmarc-reports@contoso.com, you get a TXT on _dmarc.contoso.com that starts v=DMARC1; p=none; rua=mailto:dmarc-reports@contoso.com. After reports show only authorised senders, change p to quarantine, then reject.

Guides and next steps

Privacy note

Generation runs in your browser. We do not send report addresses to our servers.

Frequently asked questions

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