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: 4.2.1.254/31
Addresses: 2 (2¹)
First IP: 4.2.1.254 (254.1.2.4.in-addr.arpa)
Last IP: 4.2.1.255 (255.1.2.4.in-addr.arpa)

Owned By: Level 3
/8 Operated By: ARIN

Related Networks

4.0.0.0/8
3.0.0.0/8
5.0.0.0/8
4.2.1.252/30
4.2.1.254/32
4.2.1.255/32

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