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: 127.128.0.4/31
Addresses: 2 (2¹)
First IP: 127.128.0.4 (4.0.128.127.in-addr.arpa)
Last IP: 127.128.0.5 (5.0.128.127.in-addr.arpa)

Owned By: IANA (Loopback)
/8 Operated By: IANA (Loopback)

Related Networks

127.0.0.0/8
126.0.0.0/8
128.0.0.0/8
127.128.0.4/30
127.128.0.4/32
127.128.0.5/32

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