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ICANN LookupIPNetInfo
Free

Free public lookup service run by ICANN.

 Free

Freeware from NirSoft that may be redistributed free of charge.

Web Windows
  • Run by ICANN rather than a registrar or advertiser
  • Uses RDAP instead of scraping WHOIS
  • Extracts IP addresses from pasted email headers
  • Queries all five regional internet registries
  • Only shows registration data, with no DNS or mail diagnostics
  • Needs an internet connection and outgoing access to port 43
  • Official requirements list Windows 98 to Windows 10 only
Web application Downloadable app
Closed source Closed source
License not stated License: Freeware
Not stated if an account is needed No account needed
Needs internet Needs internet

Checked September 23, 2026

Checked October 8, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.