gnu-ipcalc

Modern network address calculation tool for IPv4 and IPv6

This is a modern tool to assist in network address calculations for IPv4 and IPv6. It acts both as a tool to output human readable information about a network or address, as well as a tool suitable to be used by scripts or other programs. It supports printing a summary about the provided network address, multiple command line options per information to be printed, transparent IPv6 support, and in addition it will use libGeoIP if available to provide geographic information.