Master IP Subnet Calculations on Linux with Sipcalc – Installation & Usage Guide

Installation

Sipcalc is a command‑line IP subnet calculator supporting IPv4 and IPv6. To use it on CentOS 8, first enable the EPEL repository and then install the package:

[root@localhost ~]# yum -y install epel-release
[root@localhost ~]# yum -y install sipcalc

Basic CIDR Calculation ( /24 example )

Running sipcalc 192.168.10.0/24 prints a detailed breakdown of the network, including host address, network address, mask (decimal, hex, and bits), broadcast address, Cisco wildcard, total addresses, range, and usable range.

[root@localhost ~]# sipcalc 192.168.10.0/24
-[ipv4 : 192.168.10.0/24] - 0

[CIDR]
Host address  - 192.168.10.0
Host address (decimal) - 3232238080
Host address (hex) - C0A80A00
Network address  - 192.168.10.0
Network mask  - 255.255.255.0
Network mask (bits) - 24
Network mask (hex) - FFFFFF00
Broadcast address - 192.168.10.255
Cisco wildcard  - 0.0.0.255
Addresses in network - 256
Network range  - 192.168.10.0 - 192.168.10.255
Usable range  - 192.168.10.1 - 192.168.10.254

The output confirms the broadcast address, reverse mask, network range, and usable IP range for the /24 subnet.

Extended Information with -a Option

Adding the -a flag shows both classful and classless (CIDR) binary representations of the network and mask.

[root@localhost ~]# sipcalc -a 192.168.10.0/24
...[output includes Classful bitmaps and CIDR bitmaps with binary strings]...

Subnet Listing for a /27 Network

For a network with a 27‑bit mask, Sipcalc reports the smaller address pool and, with -a, lists all possible sub‑networks within the range.

[root@localhost ~]# sipcalc 192.168.10.0/27
-[ipv4 : 192.168.10.0/27] - 0

[CIDR]
Host address  - 192.168.10.0
Network mask  - 255.255.255.224
Network mask (bits) - 27
Broadcast address - 192.168.10.31
Addresses in network - 32
Network range  - 192.168.10.0 - 192.168.10.31
Usable range  - 192.168.10.1 - 192.168.10.30

[root@localhost ~]# sipcalc 192.168.10.0/27 -a
...[output includes Classful, CIDR, binary bitmaps, and a list of all sub‑networks from 192.168.10.0‑31 up to 192.168.10.224‑255]...

This demonstrates how Sipcalc can enumerate each /27 block within a larger /24 space, showing current and subsequent sub‑net ranges.