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: 17.128.1.21/32
Addresses: 1 (2⁰)
First IP: 17.128.1.21 (21.1.128.17.in-addr.arpa)
Last IP: 17.128.1.21 (21.1.128.17.in-addr.arpa)

/8 Operated By: Apple Inc.

Related Networks

17.0.0.0/8
16.0.0.0/8
18.0.0.0/8
17.128.1.20/31

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