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: 18.0.16.0/21
Addresses: 2048 (2¹¹)
First IP: 18.0.16.0 (0.16.0.18.in-addr.arpa)
Last IP: 18.0.23.255 (255.23.0.18.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
18.0.16.0/20
18.0.16.0/32
18.0.23.255/32

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