sipcalc est un outil en ligne de commande bien pratique pour manipuler les adresses IP et leurs masques. Il est disponible sur toutes les bonnes distributions GNU & Linux.

En IPv4

$ sipcalc 192.168.1.24 255.255.255.240
-[ipv4 : 192.168.1.24 255.255.255.240] - 0

[CIDR]
Host address		- 192.168.1.24
Host address (decimal)	- 3232235800
Host address (hex)	- C0A80118
Network address		- 192.168.1.16
Network mask		- 255.255.255.240
Network mask (bits)	- 28
Network mask (hex)	- FFFFFFF0
Broadcast address	- 192.168.1.31
Cisco wildcard		- 0.0.0.15
Addresses in network	- 16
Network range		- 192.168.1.16 - 192.168.1.31
Usable range		- 192.168.1.17 - 192.168.1.30

En IPv4 avec un masque CIDR

$ sipcalc 192.168.1.24/30
-[ipv4 : 192.168.1.24/30] - 0

[CIDR]
Host address		- 192.168.1.24
Host address (decimal)	- 3232235800
Host address (hex)	- C0A80118
Network address		- 192.168.1.24
Network mask		- 255.255.255.252
Network mask (bits)	- 30
Network mask (hex)	- FFFFFFFC
Broadcast address	- 192.168.1.27
Cisco wildcard		- 0.0.0.3
Addresses in network	- 4
Network range		- 192.168.1.24 - 192.168.1.27
Usable range		- 192.168.1.25 - 192.168.1.26

Convertir une adresse IPv4 en décimal :

$ sipcalc 192.168.1.1/32 | grep decimal | awk '{print $5}'
3232235777

En IPv6

 sipcalc 2001:200:dff:fff1:216:3eff:feb1:44d7/64
-[ipv6 : 2001:200:dff:fff1:216:3eff:feb1:44d7/64] - 0

[IPV6 INFO]
Expanded Address	- 2001:0200:0dff:fff1:0216:3eff:feb1:44d7
Compressed address	- 2001:200:dff:fff1:216:3eff:feb1:44d7
Subnet prefix (masked)	- 2001:200:dff:fff1:0:0:0:0/64
Address ID (masked)	- 0:0:0:0:216:3eff:feb1:44d7/64
Prefix address		- ffff:ffff:ffff:ffff:0:0:0:0
Prefix length		- 64
Address type		- Aggregatable Global Unicast Addresses
Network range		- 2001:0200:0dff:fff1:0000:0000:0000:0000 -
			  2001:0200:0dff:fff1:ffff:ffff:ffff:ffff