SendDuo

Verify your sending domain

Add a few DNS records so your emails come from your own domain and land in the inbox, not spam.

Updated October 23, 2026

SendDuo sends every email from your own domain, like hello@yourshop.com. To prove the domain is yours, you add a few records to its DNS settings once. Inboxes trust signed mail, so this is also what keeps your emails out of spam.

Add your domain

  1. In SendDuo, open Settings, then Sending domains.
  2. Type your domain (for example yourshop.com) and click Add domain.
  3. SendDuo shows the records to add: three CNAME records (DKIM, which signs your emails) and one TXT record (DMARC, which tells inboxes what to do with fakes).

Use a domain you own. Free email addresses like Gmail or Yahoo cannot be used to send marketing email.

Add the records where your domain's DNS is managed

  1. Log in where you manage DNS for your domain. That is usually the company you bought the domain from (GoDaddy, Namecheap, Hostinger and so on) or your website host.
  2. Add each record exactly as SendDuo shows it. Use the Copy buttons so nothing is mistyped: the Type, the Host (or Name) and the Value (or Points to).
  3. Come back to SendDuo and click Check now.
Tip: Many DNS providers add your domain to the Host for you. If SendDuo shows abc._domainkey.yourshop.com, type only abc._domainkey in the Name field. If a record is rejected or never shows as found, this is the most common reason.
Tip: On Cloudflare, the Host goes in Name and the value in Target (CNAME) or Content (TXT). Set Proxy status to DNS only (grey cloud).

How long it takes

Most domains verify within an hour; some take up to a day while DNS changes spread. You do not need to keep the page open: SendDuo checks automatically every 10 minutes for 72 hours and emails you when the domain is verified.

If the records are not found within 72 hours, checking stops. Fix the records, then click Start over on the domain's page to check again.

Optional: custom MAIL FROM

Under Improve deliverability (optional) you can enable a custom MAIL FROM domain. Some inboxes rate this slightly higher. It never blocks verification, so you can skip it or add it later.

Then set your sender address

Once the domain is verified, use it in your sender details. See Set up your sender details.

Careful: Never delete DNS records your email inbox already uses (such as its MX records). Only add the new ones.

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