Find all hostnames and domains associated with an IP address using PTR (reverse DNS) records. Discover what other sites share the same server.
A reverse IP lookup finds all domain names hosted on a given IP address. Web servers often host dozens or hundreds of websites on a single IP (virtual hosting). By querying a reverse-IP database you can discover the full list of domains sharing that server — useful for competitive research, security investigations, and spam analysis.
Identify whether a suspicious IP is hosting other malicious or phishing domains under the same server infrastructure.
Discover what other websites a competitor's hosting provider serves — useful for understanding infrastructure choices.
Shared IPs that host many unrelated domains may indicate a bulletproof hosting provider commonly used for spam or fraud operations.
If one domain on a shared IP gets blacklisted, all co-hosted domains may suffer. A reverse lookup reveals your neighbours.
Separate from a shared-hosting lookup, Reverse DNS (rDNS) maps an IP address to a hostname via a PTR record in the in-addr.arpa DNS zone. ISPs configure PTR records for their address blocks; they are commonly used in email authentication and server identification.
No. PTR records are optional and must be configured by the ISP or IP block owner. Many consumer IPs and cloud instances have generic PTR records or none at all.
Virtual hosting (HTTP/1.1 Host header or SNI for HTTPS) allows a single server to serve many websites. It is economical and common on shared hosting platforms.