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Reverse DNS lookup

PTR + forward check

Find the hostname published for a public IP address and check whether that hostname resolves back to the same address.

Only public address literals are accepted. PTR responses are cached for up to one hour; all DNS answers use Cloudflare 1.1.1.1.

Enter a public IP addressResults appear here without being added to a saved lookup history.

PTR and forward-confirmed reverse DNS

A PTR record maps an IP address to a hostname. Forward-confirmed reverse DNS (FCrDNS) additionally requires that hostname's A or AAAA records to include the original address.

Mail systems often use reverse DNS as one reputation signal, but a matching PTR alone does not prove identity, ownership, or trustworthy mail. Resolver timeouts are reported as inconclusive rather than as a missing record.

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