Sipcalc is an "advanced" console based ip subnet calculator.
[NOTE: The web (cgi) version of sipcalc has been removed from the tarball due to lack of time and interest in keeping it up to date with the console version. It will hopefully return in a new and improved form in the near future.]
Update: The sipcalc license has been changed from GPL to BSD in release 1.1.2, see COPYING in the tarball for further details.
Latest release, 20130114, version 1.1.6.
Sipcalc current feature list [semi complete].
Sipcalc help output.
Sipcalc sample run.
Sipcalc related links.
I'd love to hear from anyone out there using sipcalc, so don't hestitate to drop me a mail.
Direct questions, comments, bugreports to Simon Ekstrand, email@example.com