CIDR / Subnet Calculator

Use this CIDR calculator online to find subnet mask, network address, broadcast address, and host range for IPv4 addresses.

IP Address

Subnet Mask / CIDR

Network Address

192.168.1.0

Broadcast Address

192.168.1.255

Subnet Mask

255.255.255.0

CIDR Notation

/24

First Host

192.168.1.1

Last Host

192.168.1.254

Total Hosts

256

Wildcard Mask

0.0.0.255

What this CIDR calculator provides

This CIDR calculator computes subnet masks, network addresses, broadcast addresses, and usable host ranges for IPv4 networks. It works as an online subnet calculator for quick planning and validation.

Where CIDR and subnet planning helps

Plan VLAN and office network segmentation
Calculate usable host count before provisioning
Validate CIDR ranges for firewall and routing rules
Prepare network documentation for operations and support

Related network tools

IP range tool DNS lookup Reverse DNS

How to use?

Enter the IP address.

Select the subnet mask or CIDR prefix (e.g., /24).

Review the calculated network details.

Frequently Asked Questions

What is subnetting?

Subnetting is the process of dividing a large network into smaller and more manageable sub-networks.

What does a CIDR calculator show?

A CIDR calculator shows the subnet mask, network address, broadcast address, and the first and last usable host for the selected prefix.