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: 199.128.2.40/31
Addresses: 2 (2¹)
First IP: 199.128.2.40 (40.2.128.199.in-addr.arpa)
Last IP: 199.128.2.41 (41.2.128.199.in-addr.arpa)

/8 Operated By: ARIN

Related Networks

199.0.0.0/8
198.0.0.0/8
200.0.0.0/8
199.128.2.40/30
199.128.2.40/32
199.128.2.41/32

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