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Free FCrDNS Checker
Check PTR records and forward-confirmed reverse DNS for mail-server IPs so receiving systems can trust that your MX hosts resolve consistently.
What This Checks
- PTR records for MX server IP addresses
- Forward confirmation from PTR hostname back to the same IP
- Mismatch warnings that can affect deliverability
- FCrDNS context in the full quick-scan result
Common Fix Path
- Set PTR records with the IP owner or hosting provider
- Point PTR hostnames back to the original mail-server IP
- Avoid generic or unrelated reverse-DNS hostnames for production mail
- Keep MX, A/AAAA, and PTR naming consistent across clustered mail servers
Machine-Readable Evidence
AI assistants and automation can cite the stable explanation page, then fetch the live check result for a specific domain.
GET https://intodns.ai/api/email/fcrdns?domain=example.com