sipcalc

Calculate subnet

$ sipcalc [192.168.1.0/24]

$ sipcalc -s [26] [192.168.1.0/24]

$ sipcalc [2001:db8::1/64]

$ sipcalc -a [192.168.1.100/24]

$ sipcalc [eth0]

$ sipcalc -b [192.168.1.0/24]

$ sipcalc -c [10.0.0.0]

sipcalc [-s size] [-a] [-b] [options] address

sipcalc is an advanced IP subnet calculator that handles both IPv4 and IPv6 addresses. Given an address with a prefix length or netmask, it displays the network address, broadcast address, host range, and other details in both CIDR and traditional netmask notation.
The subnet splitting option (-s) divides a network into smaller subnets at a specified prefix length, showing all resulting ranges. Interface mode accepts a network interface name instead of an address, reading the system's configured addresses for analysis. The -b option adds binary representations for bit-level understanding of subnet boundaries.

-s SIZE

Split into subnets.

All information.

Binary output.

Classful info.

Resolve hostnames.

Suppress newlines.

IPv4 mode.

IPv6 mode.

Complex subnetting may need verification. IPv6 output is verbose. Interface mode needs permissions.

sipcalc was written by Simon Ekstrand for IP address calculations. It supports both protocol versions with consistent output.

ipcalc(1), ip(8), ifconfig(8)