IPv4 Subnet Calculator

This calculator and tool allows you to type an IP address in and get information on a particular subnet. Enter an IP or range in CIDR notation.

Network: 231.128.1.242/31
Addresses: 2 (2¹)
First IP: 231.128.1.242 (242.1.128.231.in-addr.arpa)
Last IP: 231.128.1.243 (243.1.128.231.in-addr.arpa)

/8 Operated By: Multicast

Related Networks

231.0.0.0/8
230.0.0.0/8
232.0.0.0/8
231.128.1.240/30
231.128.1.242/32
231.128.1.243/32

You can also use some of the other examples such as:

0.0.0.0/0
1.0.0.0/8
127.0.0.1
30.0.0.0/8
192.168.0.0/16