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: 66.128.1.221/32
Addresses: 1 (2⁰)
First IP: 66.128.1.221 (221.1.128.66.in-addr.arpa)
Last IP: 66.128.1.221 (221.1.128.66.in-addr.arpa)

/8 Operated By: ARIN

Related Networks

66.0.0.0/8
65.0.0.0/8
67.0.0.0/8
66.128.1.220/31

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