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: 3.128.12.0/23
Addresses: 512 (2⁹)
First IP: 3.128.12.0 (0.12.128.3.in-addr.arpa)
Last IP: 3.128.13.255 (255.13.128.3.in-addr.arpa)

/8 Operated By: ARIN

Related Networks

3.0.0.0/8
2.0.0.0/8
4.0.0.0/8
3.128.12.0/22
3.128.12.0/32
3.128.13.255/32

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