Although Google has long supported DMARC, some Google applications still can't send DMARC-compliant emails using SPF.

For Google Suite customers using their own domains, emails from Google's apps such as Docs, Sheets, Slides, Gmail API, and Calendar will use a domain that points back to Google, not your own domain. This creates an alignment issue for SPF, which can cause DMARC failures if your policy is set to p=quarantine or p=reject and DKIM isn't properly configured. As a result, your emails may fail DMARC checks, and Google Calendar invites might be blocked.

To make sure your Google Calendar invites reach their intended recipients, follow these steps to set up DKIM signing:

  • Access the Gmail administration panel in Google Suite.
  • Click on Authenticate Email.
  • Generate a new DKIM record:
    • When creating the DKIM key, you will need to select the bit strength. A bit strength of 2048 is recommended for better security. However, not all domain DNS providers support this size, so confirm with your DNS provider or administrator.
    • You'll also need to choose a DKIM prefix selector. The default value is google, and it's recommended to keep it as is.
  • Copy the DKIM record value and publish it with your domain's DNS provider.

Note: If DKIM signing is already set up for your Google Workspace account due to using Gmail, you don't need to configure it separately for Google Calendar.

For more information on DKIM setup and verification, refer to Google's support documentation.

We understand that customers aim for 100% DMARC compliance using both SPF and DKIM. However, due to how Google sends Calendar invites and emails from other apps, full compliance with both methods isn't currently possible. DKIM is the only viable solution.

If you need assistance getting Google Calendar invitations and emails from other Google applications to pass DMARC, consult your email administrator or Google's official resources.

For help with DMARC monitoring, deployment, or compliance, you can register for a free 30-day trial, and we’ll guide you through the process.