Subnet Calculator

Calculate subnet masks, network addresses, and host ranges

What is a Subnet Calculator?

A Subnet Calculator divides an IP network into sub-networks (subnets). It calculates the subnet mask, network address, broadcast address, and usable host range for any CIDR notation.

How to Calculate a Subnet

Frequently Asked Questions

What is CIDR notation?

CIDR (Classless Inter-Domain Routing) notation uses a slash followed by a number (e.g., /24) to indicate how many bits are used for the network portion of an IP address.

How many hosts in a /24 subnet?

A /24 subnet has 256 total addresses, with 254 usable host addresses (excluding network and broadcast addresses).