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  1. Tools
  2. rDNS Lookup

Reverse DNS Lookup

Reverse DNS resolution (rDNS) is a technique used to determine the hostname associated with an IP address. This is done searching hostname registry and registrar tables for PTR records.

RFC 1912 recommends that "for every IP address, there should be a matching PTR record," but it is not a requirement. Consequently, not all IP addresses have a hostname associated with them. In other words, it's a reverse version of the standard "forward" DNS lookup (an IP address from a domain name).

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CLI

The official CLI for the IPinfo supports nearly every feature and API we offer.

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Pingable IP Finder

Pingable IP address lookup is a free tool to help you find IP addresses that can be pinged using the ICMP protocol.

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