DomainKeys Identified Mail (DKIM) is an email authentication method that helps protect your emails from being marked as spam or spoofed. Setting up DKIM for your custom domain in SendX ensures that your emails are trusted, secure, and land in your recipients' inboxes.
Before You Begin
Before setting up DKIM:
Ensure you have access to your domain’s DNS settings (via your hosting provider or domain registrar, such as GoDaddy or Cloudflare).
You should know the subdomain you want to use for email sending
You must have a SendX account with admin access
What Is a Custom Domain or Subdomain?
A custom domain is your company’s web domain, such as
yourcompany.com.A subdomain is a subset of that domain, typically used to send emails, such as
news.yourcompany.comoremail.yourcompany.com.
Using a subdomain allows you to isolate your email activity from your main domain, improve deliverability, and maintain a clean sender reputation.
Step-by-Step Instructions
1. Log in to SendX
Open your SendX dashboard
Click on Settings from the main menu
2. Navigate to Domain Setup
Inside Settings, go to the Setup section
Click on Domain
Scroll to the bottom of the page until you see the Custom Domain section
3. Add Your Subdomain
Click on the Custom Domain option
Enter the subdomain you want to whitelist (e.g., techsolutions.saas.ai)
Click Add
4. DKIM & DNS Records Are Generated
Once the subdomain is added, DNS records (including CNAME) will be automatically generated for you
These records will need to be copied and added to your domain's DNS settings
5. Update DNS Settings
Go to your domain registrar (e.g., GoDaddy, Namecheap, Cloudflare)
Access the DNS management section
Add each of the DNS records exactly as provided in SendX:
CNAME records
Note: DNS updates may take up to 24–48 hours to fully propagate.
6. Domain Whitelisting is Completed
After the DNS records are added and verified, your subdomain will be whitelisted and ready for use
You can now send campaigns through your verified custom domain with improved inboxing and domain reputation
Tips & Best Practices
✅ Use a subdomain like
news.yourdomain.comfor email marketing to protect your root domain reputation🔄 Verify DNS propagation using tools like MXToolbox to ensure your DKIM is set up correctly
🕒 Wait for propagation before sending high-volume campaigns (it may take up to 24–48 hours)
🛡️ Combine DKIM with SPF and DMARC for stronger email authentication and protection against spoofing
📧 Test your domain by sending test campaigns to verify inbox placement
Conclusion
Setting up DKIM for your custom domain is a crucial step in maximizing your email deliverability and maintaining sender trust. With SendX, the process is streamlined and simple. Follow these steps, and your emails will be authenticated, whitelisted, and ready to perform.
Need help with DNS or domain configuration? Don’t hesitate to reach out to the SendX support team for assistance!