All ESPs
Newsletter
Kit (ConvertKit)
Kit (formerly ConvertKit) targets creators and newsletter operators. Authentication uses CNAME-based DKIM and a custom domain include.
DNS records to publish
| Type | Host | Value |
|---|---|---|
| CNAME | ck._domainkey | dkim.convertkit-mail.comDKIM |
| CNAME | convertkit-mail.comTracking domain |
Authentication setup
SPF
Optional; Kit aligns DKIM by default.
DKIM
Publish the CNAME shown in the custom-domain setup.
DMARC
Standard rollout.
Deliverability tips
- Use the cold-subscriber sunset feature to suppress contacts who haven't opened in 90+ days.
- Verify the custom sending domain before launching paid recommendations or Sparkloop integrations.
- Avoid 'inbox tester' style services — they inflate open rates and hurt machine-learning-based filters.