Reverse IP Lookup

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Find all domains hosted on a given IP address with a quick reverse IP search. Paste an IPv4 or IPv6 and instantly see the hostnames that resolve to it. Use this reverse IP lookup to audit shared hosting, discover “IP neighbors,” investigate spam sources, or map a company’s web footprint. If you need ownership data or PTR verification, see the reverse DNS (PTR) lookup notes below.

What is a Reverse IP Lookup?

A reverse IP lookup enumerates domains hosted on the same IP address. Unlike a forward DNS query (domain → IP), this does the opposite: IP → hostnames. Results are built by aggregating DNS data (A/AAAA records), historical observations, and crawled indexes. It’s commonly called a “find websites on an IP” tool, “IP to domain checker”, or “shared host checker.”

Why and when to use it

Security & DFIR: Uncover other sites on a malicious IP, pivot during investigations, or spot suspicious clusters.
SEO & Competitive research: See what else a competitor hosts on the same server or identify network peers.
Ops & Migrations: Validate that only the expected domains point to a new server after a cutover.
Abuse & Reputation: Check if your site shares an address with spammy neighbors that may affect IP reputation.

How to use the Reverse IP Lookup (step-by-step)

Enter an IP address (e.g., 93.184.216.34 or 2606:2800:220:1:248:1893:25c8:1946).
Click Search. We enumerate current and known hostnames pointing to that IP.
Use filters (TLD, substring, recently seen) to refine the list and export as CSV/JSON.

Reverse IP vs. Reverse DNS (PTR)

Reverse IP lookup lists many domains hosted on an IP (many-to-one). Reverse DNS lookup (PTR) returns the canonical hostname for an IP (one record, sometimes none). For email servers, PTR alignment is critical—pair this tool with our PTR record checker to verify rDNS for deliverability.

Who uses this tool?

Security analysts mapping attacker infrastructure and related assets.
Network & DevOps teams confirming post-migration DNS hygiene.
SEOs & marketers exploring websites hosted on the same IP or neighbor domains.
Domain investors researching portfolios clustered on a server.

Limitations & caveats

CDNs & anycast: Popular CDNs host thousands of domains per IP; reverse IP results will be very large and change often.
Virtual hosting/SNI: Multiple domains share the same web server IP—this is normal and not proof of ownership link.
Historical vs. live: Some domains may be historical (previously pointed to the IP). Use the “recently seen” filter for fresher data.
IPv6 scope: IPv6 blocks are vast; many hosts use distinct v6 addresses, so results may be sparse compared to IPv4.

Best practices

Combine with forward lookups: Verify that each listed hostname still resolves to the target IP.
Check PTR for mail servers: Use reverse DNS (PTR) lookup to confirm rDNS & align with SPF/DKIM/DMARC.
Whitelist your own assets: Tag expected domains so new, unexpected arrivals stand out.
Beware false associations: Shared IP ≠ shared ownership. Confirm with WHOIS, TLS certs, or web content.

Examples

# Input (IPv4) 93.184.216.34
Output (sample)

example.com
www.example.com

assets.example-cdn.net

Input (IPv6)

2606:2800:220:1:248:1893:25c8:1946

Output (sample)

example.org
img.example.org

FAQ

Is reverse IP lookup the same as “what websites are on this server?”

Close. It lists hostnames pointing to the IP, which often indicates the same physical/virtual server. With CDNs or proxies, a single IP can front many unrelated sites.