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WHOIS LookupDomain Age CheckerSubdomain FinderIP GeolocationASN / BGP LookupIP Blacklist CheckReverse IP LookupMAC Address LookupBGP Prefix LookupRPKI / ROA CheckDomain Availability
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Reverse IP Lookup

Find all domains hosted on an IP address using passive DNS data and web crawl records.

Examples:

Enter an IP address to find all domains hosted on it

Related Tools

IP Geolocation

Look up location, ISP, ASN, timezone, and proxy detection for any IP address.

DNS Lookup

Query any DNS record type for any domain - A, AAAA, MX, TXT, CNAME, NS, SOA, CAA. Results come from our own neutral resolver.

IP Blacklist Check

Check an IPv4 address or a domain against the major DNS-based spam and abuse blocklists (DNSBLs), one or a whole list at once.

About this tool

About Reverse IP Lookup

Reverse IP lookup identifies domains that resolve (or have recently resolved) to a given IP address. Unlike forward DNS which maps a domain to an IP, reverse IP requires a database of passive DNS observations - records accumulated from web crawls and DNS monitoring sensors over time. This is useful for investigating shared hosting environments, mapping infrastructure, and security research. This tool combines three passive DNS sources, HackerTarget, CIRCL and Robtex, and shows the network the address belongs to from RIPEstat. For an IPv6 address it shows the PTR records instead, looked up through Cloudflare DNS.

Reverse IP lookup or reverse DNS?

A reverse IP lookup lists the domains whose DNS points to an IP address, such as every website hosted on one shared server. DNS itself cannot be asked which names point to an address, so the answer comes from passive DNS: a database of DNS answers recorded over time.

Reverse DNS answers a narrower question: the one name that the holder of the address has set for it, in a PTR record. A mail server usually has one; a shared web server usually has a name of its hosting company, not of the sites on it. For an IPv6 address this tool shows its PTR records, and for the PTR record of any address there is the PTR lookup.

How to use

Enter an IPv4 address and click Look Up. Results show all domains in the passive DNS sources that have pointed to that IP. For an IPv6 address, the tool shows its PTR records.

Results are not exhaustive. Dedicated servers typically return 0-1 domains. Shared hosting and CDN edge IPs can return hundreds. A domain currently pointing to the IP may not appear if it was never crawled, and domains that no longer point to the IP may still appear if they recently did. Results are cached for 24 hours. Common use cases: verifying shared hosting neighbors, investigating phishing infrastructure, mapping attacker-controlled domains during incident response, and competitive research on hosting patterns.