FAHAQ

IP Subnet Calculator

Work out network, broadcast and host range from an IP.

Network address
192.168.1.0
Broadcast address
192.168.1.255
Subnet mask
255.255.255.0
CIDR
/24
Host range
192.168.1.1 – 192.168.1.254
Usable hosts
254

Free online IP subnet calculator. Enter an IPv4 address and subnet mask (dotted or CIDR) to get the network and broadcast addresses, usable host range, host count and CIDR notation. Runs in your browser.

How to use the IP Subnet Calculator

  1. 01Enter an IPv4 address.
  2. 02Enter a subnet mask as dotted decimal (255.255.255.0) or CIDR (/24).
  3. 03Read off the network, broadcast, host range and usable host count.

Frequently asked questions

How is the usable host count calculated?

For a normal subnet it is the total addresses minus two — one for the network address and one for the broadcast address. A /31 or /32 has no usable host range in the traditional sense.

Can I enter the mask as a slash?

Yes — the mask field accepts either dotted decimal (255.255.255.0) or CIDR (/24 or 24), so use whichever you have.