Reverse IP Lookup

About Reverse IP Lookup

Reverse IP Lookup takes an IPv4 address and lists the domain names known to be hosted on it, together with its PTR record. On shared hosting a single address can serve hundreds of unrelated sites, so this shows you the neighbors, which matters for security reviews and for understanding an address's reputation.

How to use it

1. Enter a public IPv4 address such as 8.8.8.8 in the IP Address box. IPv6 is not accepted.
2. Press Reverse Lookup. Our server queries the address's PTR record and asks an external data source for hosted domains.
3. Read the Summary card: the IP, its PTR Record, the Source of the data and the number of Domains Found.
4. Browse the Domains on this IP table for the hostnames themselves.

When to use it

• Discovering which other websites share a server with one you run on cheap shared hosting.
• Investigating whether a blacklisted address also carries unrelated business domains.
• Mapping an attacker's infrastructure by listing the sites served from one address.
• Checking the reverse DNS name that mail servers will see when your machine connects.

Questions about Reverse IP Lookup

What does the Source field tell me?

It says where the list came from. HackerTarget means the domain list came from that data source, DNS PTR record means only the address's PTR entry was found, and No data means neither returned anything.

Why is the list short or empty?

Reverse IP data is collected by scanning and passive observation, so it is never complete. Sites behind CDNs share addresses with thousands of others and are usually not listed. If the external source fails or hits its quota, only the PTR result remains.

What is a PTR record?

It is the reverse DNS name the address's owner published, such as mail.example.com. It is set by whoever controls the IP block, so it often shows the hosting provider's generic name rather than your domain.

Does the address leave my device?

Yes. It goes to our server, which passes it to an outside data provider to obtain the domain list. Lookups are capped at 10 per minute because that provider's quota is shared.

Can I enter a domain name instead?

Not here. It requires a dotted IPv4 address. To go from a domain to its address, use DNS Lookup first and paste the A record back in.

Related tools

• IP LookupLook up information about an IP address
• DNS LookupLook up DNS records for a domain
• WHOIS LookupLook up WHOIS information for a domain
• PingPing a domain or IP address
• SSL LookupLook up SSL certificate information for a domain
• HTTP Headers LookupLook up HTTP headers for a URL