This article is part of a series dedicated to helping you set up DKIM, SPF, and DMARC records to authenticate the custom domain email addresses you use to send emails with Kartra.

What is DKIM?

DKIM (DomainKeys Identified Mail) is an email authentication method used to confirm that a message was sent by the domain attached as the sender. Think of it as a digital signature that cannot be forged. It is published in the DNS settings for the domain.

In Kartra, you can use KartraMail as your default email gateway, integrate a third-party SMTP service, or use a combination of both. The location where you will start your domain authentication depends on which gateway(s) you use.

In this article:

  1. What is DKIM?
  2. KartraMail Authentication
  3. Integrated SMTP Authentication

Kartra generates DKIM records for domains used with KartraMail, which are then added to the DNS settings for your email domain. This creates the necessary connection that authorizes KartraMail to send emails from your domain. 

Take Note
  • DKIM records are authentication keys used to prove that you own the domain you are using to send email.
  • When looking at your email gateway in Kartra, look at the configuration for the send-from address. That is the sender domain that you need to authenticate.
  • If you change the send-from address to one with a new domain, you will need to complete the authentication process again to verify the new domain.
  • If you send emails from more than one domain, each one must be added to your Kartra account and authenticated separately.

KartraMail Authentication

Get DKIM records from your Kartra account to authenticate mail sent with a custom sender domain via KartraMail.

Complete the DKIM configuration in two places:

In Kartra:

  1. Click your avatar in the top right corner of your account.
  2. Select KartraMail DKIM.
  3. In the bottom right, click + DKIM records.
    New DKIM Record Configuration Box
  4. Enter your email sender domain, formatted as Do not include “www” or any other characters.
  5. Click Add DKIM record.
    The next screen includes configuration instructions and the Kartra-generated DKIM records for your account.
    DKIM CNAME Records Generated for you by KartraAbove: Example of DKIM records generated by Kartra. Add DKIM entries to your account to generate unique records for each of your sending domain(s).
  6. Log in to your domain registrar account to add and publish the CNAME records before closing the DKIM details screen.

In your domain registrar account:

  1. Go to the DNS Settings or DNS Management area.
  2. Locate the domain(s) you use to send email.
  3. Add a new CNAME record to the domain.
  4. Paste the “Host” and Points to” values from the first record provided in Kartra into the corresponding fields for the new CNAME record.
    Example of DKIM CNAME records in GoDaddy domain managementExample of DKIM CNAME records in GoDaddy domain management
  5. Repeat to create three total CNAME recordswith the details from your Kartra account.
    • IMPORTANT: Some domain providers will allow you to paste the complete Host value provided by Kartra (ie,, and some will add the domain portion of the value for you.
      If the domain portion is added for you, you will only add the prefix portion of the Kartra-generated Host value in the field (ie, sk48601, as shown in the GoDaddy example image above). If you are not sure which method your domain provider requires, please contact their support for help.
  6. Save your DNS changes.

Go back to Kartra and click the confirmation checkbox at the bottom of the DKIM details window before clicking Finish.

Pro tip

  • The interface and terminology for DNS settings will vary depending on what service you use to manage your domain.
  • When browsing your domain registrar’s knowledge base, search for help with adding domain records in the CNAME format.

Allow up to 48 hours for the DKIM record to be verified. While this is in process, the domain entry will display a yellow “Pending validation” status.

The displayed status will update automatically based on whether the domain is validated:

  • Connected: The domain has been validated and DKIM records are successfully detected.
  • Error: The domain could not be validated. Check the error message for help.

Examples of domain connection status

Examples of domain connection status

Integrated SMTP Authentication

Third-party SMTP providers can be used to deliver mail from your Kartra account instead of or in addition to KartraMail.

If you are exclusively using an integrated SMTP, no DKIM configuration is needed in Kartra.

Instead, go to the help resources for your integrated SMTP to learn how to authenticate your sender domain for their service. The links below are provided for your convenience. For assistance with any of these processes, please contact the provider directly.

Kartra integration partners: