What is a reverse IP lookup?

A reverse IP lookup finds the domain names that resolve to a given IP address, which is useful for identifying sites that share the same server or hosting infrastructure.

Why are some domains missing from the results?

Reverse IP data comes from a public dataset that does not see every domain. Large CDNs and shared hosts may return partial lists, and very large IPs can be truncated.

Why did the lookup return only one domain?

The address is likely a dedicated IP serving a single site, or the dataset has limited coverage for it. Dedicated hosting and small servers naturally return very short lists.

Why are there no results for a Cloudflare IP?

CDN edge IPs front huge numbers of sites and are intentionally opaque, so reverse IP data for them reflects the CDN rather than a meaningful list of owners.

Is reverse IP lookup the same as reverse DNS?

No. Reverse DNS returns the single PTR hostname an IP owner published, while reverse IP lists the many website domains observed pointing at that address.

Does this scan the target server?

No. Results come from a passive public dataset, so the lookup never sends traffic to or probes the IP you enter.

Reverse IP Lookup

Enter an IP address to list the domains known to be hosted on it.

Updated June 2026

IP Address

Server processing — results come from a shared public dataset and may be incomplete for large hosts.

How to use Reverse IP Lookup

The Reverse IP Lookup tool finds other domains and websites that are hosted on the same IP address as the one you enter. Many sites share a single server or load balancer — especially on shared hosting and some CDNs — so a single IP can front dozens or hundreds of unrelated domains. Discovering those neighbours is useful for security research, for understanding how an organization’s infrastructure is laid out, and for spotting sites that may be affected by the same server-level problem. Results are drawn from a large passive dataset, so the lookup never probes the target server directly.

Enter the IPv4 address you want to investigate.
Click Lookup to query the reverse-IP dataset.
Review the list of domains reported on that address.
Note the total count to gauge how crowded the server is.
Cross-check interesting domains with WHOIS or DNS tools.

Why many domains share one IP

Shared hosting plans place many customers on a single server to keep costs low, and the web server uses the HTTP Host header (or TLS SNI) to decide which site to serve for each request. CDNs and reverse proxies take this further, fronting thousands of origins behind a small pool of edge IPs. As a result, a reverse IP lookup on a shared or CDN address can return a long list of unrelated domains, while a dedicated server or a site on its own IP may return only one or two.

Limits of reverse IP data

Reverse IP results come from a passive dataset built by crawling and DNS observation, not from the server itself, so they are a strong sample rather than a guaranteed complete list. Large CDNs such as Cloudflare or Fastly share edge IPs across enormous numbers of sites, so a lookup there reflects the CDN rather than a single owner. Treat the output as a research lead and confirm relationships with WHOIS, certificate transparency, or DNS records before drawing conclusions.

Typical hosting scenarios
Scenario	Reverse IP result
Dedicated server	One or a few related domains
Shared hosting	Many unrelated domains
CDN edge IP	Sites belonging to the CDN, not one owner

Glossary

Reverse IP: Finding the domains that resolve to a given IP address.
Shared hosting: A plan where many websites run on one server and IP address.
Host header: The HTTP header a server uses to pick which site to serve on a shared IP.
SNI: Server Name Indication — the TLS field that selects a site on a shared IP.
CDN: Content Delivery Network that fronts many origins behind shared edge IPs.

Frequently Asked Questions

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Why use Reverse IP Lookup?

Reveal other domains co-hosted on a single IP address
Understand whether a site is on shared or dedicated hosting
Spot related or sister sites operated from the same server
Gather infrastructure context for security and recon work

Common use cases

Check whether a website shares a server with risky or spammy neighbours
Map the other properties an organization runs from one IP address
Investigate the footprint of a hosting provider during security research
Find sister sites that may share a vulnerability or misconfiguration
Decide if moving to dedicated hosting is worthwhile for reputation reasons

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