Reverse IP Lookup
What is Reverse IP Lookup?
Reverse IP Lookup identifies all domains hosted on a specific IP address and retrieves the server's PTR hostname record. Our tool queries six independent data sources simultaneously — HackerTarget, YouGetSignal, RapidDNS, ViewDNS, Bing and DNSlytics — then merges and deduplicates results for maximum coverage. Results are cached for 24 hours.
Good test IPs: Try 199.59.243.200 (shared WordPress hosting), 104.21.0.1 (Cloudflare shared), or any large shared hosting IP. Dedicated servers and CDN IPs will typically show fewer domains.
Key Use Cases
- SEO Analysis — check whether your IP is shared with spammy sites.
- Cybersecurity — map attacker infrastructure by correlating all domains on a suspicious IP.
- Competitor Research — discover related projects or sister sites on the same server.
- Network Audits — verify PTR records and audit IP utilisation across hosted domains.
Frequently Asked Questions
Why does the same IP show different counts on different tools?
Each data source maintains its own database, crawled at different intervals. We query all 6 and merge results, so you get more complete coverage than any single tool.
Why are no domains listed for some IPs?
Dedicated servers, CDN edge nodes, and recently assigned IPs often have no indexed domains. Shared hosting IPs (especially from providers like Namecheap, Bluehost, HostGator) typically yield hundreds of results.
Can I look up a domain instead of an IP?
Yes — enter any domain name and it will be automatically resolved to its IPv4 address before performing the lookup.
Results are cached — how do I force a fresh lookup?
Results are cached for 24 hours for performance. If you need fresh data, check back the following day.