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: 20.128.0.242/31
Addresses: 2 (2¹)
First IP: 20.128.0.242 (242.0.128.20.in-addr.arpa)
Last IP: 20.128.0.243 (243.0.128.20.in-addr.arpa)

/8 Operated By: ARIN

Related Networks

20.0.0.0/8
19.0.0.0/8
21.0.0.0/8
20.128.0.240/30
20.128.0.242/32
20.128.0.243/32

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