Reverse IP Lookup

Reverse IP Lookup answers the question "what other domains are hosted on this same IP address?" by querying datasets that map IP addresses to the domains pointing at them. You enter an IP or a domain, and the tool returns a list of co-hosted sites that share that address. This is especially common on shared hosting and certain cloud or CDN tiers where many websites resolve to a single public IP.

The technique relies on aggregated DNS and passive-collection databases rather than a live scan, because there is no protocol that directly asks an IP to enumerate its domains. The tool resolves your input to an address, then queries those datasets for known associations. Coverage varies by provider and is never exhaustive, so absence from the list does not prove a domain is not co-hosted.

Use cases include identifying neighboring sites on shared hosting for security or reputation reasons, mapping an organization's footprint when many of its properties share infrastructure, investigating spam or abuse originating from an address, and OSINT research linking related sites. It complements a Hosting Provider lookup, which tells you who owns the network, and DNS tools that confirm the underlying resolution.

Two important caveats: behind CDNs and large reverse proxies, an IP may front thousands of unrelated domains, so co-location implies nothing about a shared owner. And on dedicated or cloud-isolated hosting, a reverse IP query may legitimately return only the single domain you queried. Treat the results as leads to verify, not as proof of ownership relationships.