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IP Subnet Calculator

Calculate subnet information from IP address and CIDR notation. Get network address, broadcast address, usable host range, and total host count instantly.

Used 34.8K times today

How to Use IP Subnet Calculator

  1. 1

    Enter IP address

    Type any IPv4 address (e.g. 192.168.1.0).

  2. 2

    Enter CIDR or subnet mask

    Enter a CIDR prefix length (e.g. /24) or a subnet mask (e.g. 255.255.255.0).

  3. 3

    See subnet details

    Instantly see network address, broadcast, first/last usable hosts, and total hosts.

Frequently Asked Questions

What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation expresses a subnet as an IP address followed by a slash and the prefix length (e.g. 192.168.1.0/24). The prefix length indicates how many bits are in the network portion.
How many usable hosts does /24 give?
A /24 subnet has 256 addresses total (2^8), minus 2 for network and broadcast = 254 usable host addresses.

Embed This Tool

Add this tool to your website for free. Just copy and paste the code below:

<iframe src="https://utilko.com/embed/ip-subnet-calculator/" width="100%" height="500" frameborder="0" title="IP Subnet Calculator"></iframe>

About IP Subnet Calculator

The IP Subnet Calculator on Utilko computes all subnet parameters from an IP address and CIDR prefix. Enter any IPv4/CIDR combination to instantly see network address, broadcast address, usable host range, subnet mask, wildcard mask, and total host count.

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