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: 18.0.3.242/31
Addresses: 2 (2¹)
First IP: 18.0.3.242 (242.3.0.18.in-addr.arpa)
Last IP: 18.0.3.243 (243.3.0.18.in-addr.arpa)

Owned By: MIT
/8 Operated By: ARIN

Related Networks

18.0.0.0/8
17.0.0.0/8
19.0.0.0/8
18.0.3.240/30
18.0.3.242/32
18.0.3.243/32

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