Subnet Mask Calculator

Calculate subnets from IP + CIDR — network, broadcast, mask, wildcard and usable host count.

IP address:

CIDR prefix:

—Network

—Broadcast

—Subnet mask

—Wildcard

—Usable hosts

—Host range

How to use

Enter an IP and CIDR prefix to get the full subnet breakdown instantly.

What is CIDR?

Classless Inter-Domain Routing — the /24 in 192.168.1.0/24 means the first 24 bits are the network.

How many hosts in a /24?

254 usable hosts (256 addresses minus network and broadcast).

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