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Before you can send emails through Plunk, you must verify at least one domain. Domain verification proves that you own the domain and authorizes Plunk to send email on its behalf. Without it, emails will fail to send and your domain’s reputation cannot be protected.

Why domain verification matters

  • Deliverability: Gmail, Outlook, and other providers use DKIM and SPF to decide whether to deliver or reject email. Without these records, your emails are more likely to be marked as spam or silently dropped.
  • Anti-spoofing: DMARC alignment prevents anyone else from impersonating your domain.
  • Bounce handling: An MX record lets Plunk receive delivery failure notices and spam complaints so it can automatically manage your contact list.

Adding a domain

1

Open project settings

In the dashboard sidebar, click Settings for your project, then select the Domains tab.
2

Add your domain

Enter the domain you want to send from (e.g., yourdomain.com) and click Add domain. Plunk will generate the DNS records you need to add.
3

Add the DNS records

Log in to your DNS provider and add each record shown. See the record types below for details on what each one does.
4

Wait for verification

Plunk checks your DNS records automatically. Verification typically completes within a few minutes, but DNS propagation can take up to 72 hours depending on your provider’s TTL settings.

DNS records

Domain verification requires four DNS records. Each serves a distinct purpose.

DKIM records — 3 CNAME records

DomainKeys Identified Mail (DKIM) signs outgoing emails with a cryptographic key. Receiving mail servers use the public half of this key (stored in your DNS) to verify that the email was sent by Plunk and has not been modified in transit. Plunk provides three CNAME records for DKIM. You must add all three.
What it preventsWhy you need all three
Email spoofing and tamperingAWS SES uses three DKIM selectors for key rotation and redundancy
Spam classificationDKIM is a requirement for Gmail and Outlook’s authentication checks

SPF record — 1 TXT record

Sender Policy Framework (SPF) publishes a list of mail servers that are authorized to send email for your domain. When a receiving server checks SPF, it looks at this TXT record to decide whether the sending server (AWS SES in this case) is legitimate.
If you already have an SPF record for your domain, you may need to merge the Plunk value into the existing record rather than adding a second TXT record. Most DNS providers only allow one SPF record per domain.

Bounce handling MX record — 1 MX record

This MX record routes delivery failure notifications (bounces) and spam complaints back to Plunk. Without it, Plunk cannot automatically detect and unsubscribe contacts whose addresses are invalid or who have marked your email as spam.
This MX record is for outbound email processing (handling bounces and complaints). If you also want to receive inbound emails at your domain and trigger workflows, you need a separate inbound MX record. See Receiving emails for setup instructions.

Verification status

After adding all records, the Domains tab shows the verification status for each record individually. A record moves to Verified once Plunk detects it in DNS. You do not need all records to verify simultaneously — they are checked independently. However, you should not send email until all records are verified. Verification can take up to 72 hours if your DNS provider has a high TTL or slow propagation.

Troubleshooting

Records not verifying after 24 hours

  1. Check for typos: Copy the exact values from the Domains tab. Extra spaces or incorrect capitalization will cause failures.
  2. Check propagation: Use dig or an online DNS checker to confirm the records are live:
    dig CNAME _domainkey.yourdomain.com
    dig TXT yourdomain.com
    dig MX yourdomain.com
    
  3. Lower your TTL: A high TTL means DNS changes take longer to propagate. Temporarily lower it to 300 seconds while verifying.
  4. Contact your DNS provider: Some providers have quirks with CNAME records or require specific formatting. Check their documentation for adding CNAME and TXT records.

Emails still going to spam after verification

Domain verification is necessary but not sufficient for inbox placement. Emails can still land in spam if:
  • Your sending domain or IP has a low reputation (common with new domains)
  • Email content triggers spam filters (excessive links, suspicious keywords, missing plain-text alternative)
  • Recipients have previously marked your emails as spam
  • You are sending to large numbers of unengaged or invalid addresses
Maintain good list hygiene and start with small send volumes to build reputation gradually.

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