AcuityScan

Reverse IP Lookup

Find other domains hosted on the same IP address. Detect shared hosting environments, discover related websites, and check PTR records.

Shared hosting detectionRelated domainsPTR recordsIP resolution

Resolves the domain to its IP address, checks PTR records, and finds other domains sharing the same server.

What you get

Here's a sample of what a reverse IP lookup returns for a typical shared hosting server.

IP198.51.100.42
PTRserver42.hostingco.com
Domains Found7
Sample: Domains on 198.51.100.42
example.com
shop.example.com
anotherbusiness.com
localbakery.net
freelancer-portfolio.com
smallbiz-tools.io
community-garden.org

How it works

IP Resolution

If you enter a domain name, the tool first resolves it to its A record IP address. You can also enter an IP address directly to skip this step.

PTR Record Lookup

Checks the reverse DNS (PTR) record for the IP address. PTR records map IPs back to hostnames and reveal the server's configured hostname — often showing the hosting provider.

Shared Hosting Detection

Queries public databases to find other domains that resolve to the same IP address. If multiple unrelated domains share an IP, the site is on shared hosting.

Domain Enumeration

Lists every domain found on the IP address. This reveals what other websites share your server — useful for security assessments and understanding your hosting environment.

Hosting Provider Identification

The PTR record and IP range often reveal the hosting provider (AWS, Cloudflare, GoDaddy, etc.). This helps identify the infrastructure behind any website.

Security Implications

Shared hosting means other sites on the same server could affect your site's reputation. If a neighbor site gets blacklisted or compromised, it can impact all domains on that IP.

Common questions

What is a reverse IP lookup?
A reverse IP lookup finds all domains hosted on a given IP address. Normally, DNS maps domain names to IPs (forward lookup). Reverse IP does the opposite — starting from an IP and finding which domains point to it.
Why would I use this?
Common use cases include: checking if your site is on shared hosting (and who your neighbors are), security assessments to understand a server's exposure, competitive research to see what other sites a company hosts, and investigating suspicious IPs to see what domains they serve.
What does shared hosting mean for security?
On shared hosting, multiple websites run on the same server. If another site on your server gets hacked, sends spam, or gets the IP blacklisted, it can affect your site's email deliverability, SEO reputation, and potentially even security (in poorly isolated environments).
What is a PTR record?
A PTR (Pointer) record is the reverse DNS record for an IP address. It maps an IP back to a hostname. ISPs and hosting providers set PTR records on their IP ranges. Mail servers check PTR records as part of email authentication — a missing or mismatched PTR can cause email delivery issues.
Will this find ALL domains on an IP?
No tool can guarantee finding every domain on an IP. We query public databases and DNS records, but some domains may not be indexed. Domains behind Cloudflare or similar CDNs resolve to CDN IPs, not origin server IPs, which limits discovery.
Do I need an account?
No account required. For unlimited scans, monitoring, white-label reports, and the full Site+ Scan, see our Pro and Agency plans starting at $29/month.

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DNS LookupSubdomain FinderWHOIS LookupPort Scanner

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