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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.

  • 100% free
  • No signup
  • Runs in your browser
Common uses: subnet calculator · ip subnet calculator · cidr calculator · network calculator · subnet mask calculator

Used 53.4K 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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