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: 191.128.0.40/31
Addresses: 2 (2¹)
First IP: 191.128.0.40 (40.0.128.191.in-addr.arpa)
Last IP: 191.128.0.41 (41.0.128.191.in-addr.arpa)

/8 Operated By: LACNIC

Related Networks

191.0.0.0/8
190.0.0.0/8
192.0.0.0/8
191.128.0.40/30
191.128.0.40/32
191.128.0.41/32

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