Reverse IP lookup

The Reverse IP Lookup tool attempts to find the domain names associated with a given IP address. It performs a reverse DNS (PTR) lookup to retrieve the hostname that points to the IP. In some cases, if the IP hosts multiple websites (shared hosting), additional data sources may reveal other domains residing on the same server.

Security analysts and penetration testers use this tool during reconnaissance to discover other websites hosted on the same server as a target. If a server hosts multiple sites, one vulnerable site could potentially be used to compromise others. This helps in understanding the attack surface.

System administrators might use reverse IP lookup to verify that PTR records are correctly configured. Proper reverse DNS is important for mail server reputation—many email servers reject messages from IPs without valid PTR records. It also helps in identifying misconfigured DNS entries.

For SEO, while reverse IP lookup is less directly relevant, it can reveal if you are sharing an IP with spammy or penalized sites, which could theoretically impact your IP reputation. However, Google typically ignores this for ranking. More practically, it helps in server migration planning by confirming which domains are hosted on a specific IP before moving them.