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: 121.0.0.0/12
Addresses: 1048576 (2²⁰)
First IP: 121.0.0.0 (0.0.0.121.in-addr.arpa)
Last IP: 121.15.255.255 (255.255.15.121.in-addr.arpa)

/8 Operated By: APNIC

Related Networks

121.0.0.0/8
120.0.0.0/8
122.0.0.0/8
121.0.0.0/11
121.0.0.0/32
121.15.255.255/32

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