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IPNetInfo vs OpenRDAP: catalog facts
IPNetInfo	OpenRDAP
Free Freeware from NirSoft that may be redistributed free of charge.	Free Free and open source under the MIT License.
Windows	Windows, Linux, Command line
Extracts IP addresses from pasted email headers Queries all five regional internet registries	Supports domain, IP, autonomous system, nameserver, and entity queries. Outputs results as text or JSON, with WHOIS-style output for domain queries.
Needs an internet connection and outgoing access to port 43 Official requirements list Windows 98 to Windows 10 only	Limitations not stated
Downloadable app	Downloadable app
Closed source	Open source
License: Freeware	License: MIT
No account needed	Not stated if an account is needed
Needs internet	Not stated if it works offline
Official website Full listing and sources Checked October 8, 2026	Official website Full listing and sources Checked October 6, 2026

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