CIDR Calculator

Calculate network ranges and subnets.

Interactive

The cidr calculator workspace is being lifted from the original build.

The same logic you already rely on, dressed in the new editorial layout. Until it lands here, the notes below cover what the tool does and when it earns its keep.

Parse CIDR notation to get network address, broadcast IP, netmask, and usable host range.

Subnet details

Instantly see the first and last usable IP address for any given CIDR block.

Visual utilization

Visualize the size of the network relative to the total IPv4 address space.

When it earns its keep

Plan network subnets
Configure firewall rules
Debug IP address overlap

Questions people ask

What is /24?

A standard Class C subnet with 256 addresses (254 usable).