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: 251.128.0.0/23
Addresses: 512 (2⁹)
First IP: 251.128.0.0 (0.0.128.251.in-addr.arpa)
Last IP: 251.128.1.255 (255.1.128.251.in-addr.arpa)

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

Related Networks

251.0.0.0/8
250.0.0.0/8
252.0.0.0/8
251.128.0.0/22
251.128.0.0/32
251.128.1.255/32

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