Subnet Calculator

IP Address and Netmask:
IP Address:
Wildcard Mask:
CIDR Notation:
Network Address:
Usable Host Range:
Broadcast Address:
Binary Netmask:
Total number of hosts:
Number of usable hosts:
IP Class:

Example IP Address Inputs

IPv4 Mask Notation Mask #52Calculates a network with 52 hosts
2001:0db8:85a3::8a2e:0370:7334/64Prefix Mask
2001:0db8:85a3::/48/64Subnet the /48 network into /64 networks

URL Parameters

It is possible to add the IP address to the URL to go directly to that IP and calculate it. Each of the following URLs will work:

This allows for using keyword searches in Firefox. users can enjoy the !subnet bang command which makes use of this tool. Try !subnet

About this Subnet Calculator

This free online subnet calculator allows for the input of a netmask, a Cisco wildcard mask or /CIDR notation.
The tool also has the ability to create a random IP address which can then be calculated. This is useful when studying and learning how to subnet and example practice networks are needed.
This calculator can also be used to do reverse subnetting where the number of hosts is known but the netmask is not.
Calculator is also IPv6 ready.
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