Free tools
CNAME lookup
Enter a hostname (e.g. selector._domainkey.example.com or mail.example.com).
What this checks
CNAME chain resolution, target hostname, TTL, and CNAME-at-apex warnings where applicable.
Why it matters
Email providers often use CNAME for DKIM delegation or branded tracking links. Broken CNAMEs break authentication or click tracking.
Results
Common issues
- CNAME chains that exceed resolver limits or point to deleted targets.
- Using CNAME at the DNS apex alongside other record types.
- Provider DKIM CNAME not propagated after DNS migration.
How to fix
- Verify the full CNAME chain resolves to the expected target.
- Use provider DNS panels to republish delegated DKIM records.
- Re-run DKIM checker after CNAME updates propagate.
How MailFleet helps
When providers delegate DKIM via CNAME, MailFleet profiles note the hostnames to verify after DNS changes.
Related free tools
Delivery note: MailFleet helps users manage campaigns through their own sending providers. Delivery outcomes depend on sender reputation, DNS authentication, content quality, recipient engagement, list quality, provider rules, and mailbox filtering systems.
For regulatory context on commercial email in the United States, see the FTC CAN-SPAM compliance guide.
Frequently asked questions
CNAME at the DNS apex is generally invalid alongside other records. Use ALIAS/ANAME or provider-specific apex setup instead.
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