Reverse IP Domain Checker
This free reverse IP checker takes an IP address (or a domain, which it resolves first) and reports the reverse DNS host name, whether that name resolves back to the same address, and the network block and organisation that own it from the internet registry. It shows what public records verify, and explains why a full list of sites on a shared server needs a paid index.
Reverse IP Domain Checker
Domain and Server
About this tool
Reverse lookups answer questions that forward lookups cannot: which host name a server calls itself, whether a mail server's address has the matching reverse name that receiving servers expect, who really owns the address block behind a suspicious domain, and whether two sites are on the same machine. Hosting support, email deliverability work and link audits all lean on them.
The checker asks the resolver for the PTR record of the address, then resolves that name forward again to confirm it points back (forward-confirmed reverse DNS, the check mail servers make). It asks the regional registry, through RDAP, for the network block that contains the address and the organisation it is assigned to. When you type a domain instead of an address, the domain is resolved first and the result also says whether the reverse name matches it.
DNS has no record type that lists every domain pointing at an address. Services that show "other sites on this server" build that list by crawling the web and storing which domain resolved where, which is a large paid dataset. This tool only reports what can be verified live from public DNS and registry records, and says so plainly rather than showing a partial or stale list.
Frequently asked questions
Why does the tool not list the other domains on this IP?
Because DNS does not store that information. A reverse (PTR) record holds one name chosen by the address owner, not every domain that points there. Lists of neighbouring sites come from paid crawler indexes that record which domains resolved to which address over time, and they are often incomplete or out of date.
What is forward-confirmed reverse DNS?
The address has a PTR name, and that name resolves back to the same address. Mail servers such as Gmail and Outlook check this before accepting email, and many reject or mark as spam a sending server that fails it. If you run your own mail server, ask your host to set the PTR to your mail host name.
The reverse DNS name belongs to a hosting company, not my domain. Is that a problem?
For a website, no: visitors never see it. For a mail server it can be, because the PTR name should match the name the server uses when it sends email. On shared hosting and most cloud plans the PTR is a generic name and you cannot change it; use your provider's mail service or a dedicated address instead.
Can a reverse IP lookup reveal who owns a website?
It reveals who owns the address block, which is almost always the hosting or cloud company, not the website owner. For the owner of a domain, look at its WHOIS and RDAP registration record with the domain age checker; for the hosting company, the domain hosting checker combines several signals.
Does sharing an IP with other sites hurt SEO?
Not on its own. Most of the web shares addresses on shared hosting and CDNs, and Google has said that is fine. The exception is a network of sites that link to each other from the same server to inflate rankings, which search engines can detect; the class C IP checker helps spot such patterns in a link profile.