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: 255.128.1.56/31
Addresses: 2 (2¹)
First IP: 255.128.1.56 (56.1.128.255.in-addr.arpa)
Last IP: 255.128.1.57 (57.1.128.255.in-addr.arpa)

Owned By: IANA (Reserved (Future Use))
/8 Operated By: IANA (Reserved (Future Use))

Related Networks

255.0.0.0/8
254.0.0.0/8
255.128.1.56/30
255.128.1.56/32
255.128.1.57/32

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