Reverse DNS (PTR) Lookup
Find the hostname assigned to an IP address, with forward-confirm verification.
About this tool
Looks up the PTR record for an IP and then forward-resolves the result to confirm the mapping is bidirectional. Mail servers, in particular, are often rejected if reverse DNS does not forward-confirm.
FAQ
- Why does forward-confirm matter for mail?
- Mail servers (Gmail, Outlook, etc.) reject SMTP connections from IPs whose PTR record points to a name that does not resolve back to the same IP. This is a basic anti-spam check.