Home Subnet calculator

Subnet calculator

Network, broadcast, and the usable host span appear at once. The math stays on this screen.

  • Network
  • Broadcast
  • Mask
  • Wildcard
  • First host
  • Last host
  • Usable hosts
  • Class
  • Scope

Why this exists

Works out a range from CIDR or an IP and a mask.

Calculates an IPv4 CIDR or subnet mask. The address is not uploaded.

  1. 01How to use it

    Network, broadcast, and the usable host span appear at once. The math stays on this screen.

    Works out a range from CIDR or an IP and a mask.

  2. 02What you get

    192.168.1.0/24

    Network, broadcast, and the usable host span appear at once. The math stays on this screen.

    Entered192.168.1.0/24

    Network 192.168.1.0
    Hosts 254

  3. 03Worth knowing

    Calculates an IPv4 CIDR or subnet mask. The address is not uploaded.

Questions

Q/31?
AWorks out a range from CIDR or an IP and a mask.
QIPv6?
ANetwork, broadcast, and the usable host span appear at once. The math stays on this screen.
Qmask only?
ACalculates an IPv4 CIDR or subnet mask. The address is not uploaded.

How this page works it out

Enter an IPv4 address and a prefix after the slash, or an address and a mask. An address alone is treated as /24.

You get the network, the broadcast, the first host, the last host, and the usable count. The prefix runs from 0 to 32. IPv6 is not calculated. The 1-bits of a mask must run together from the left.

A file you choose, text you type, and a picture you make stay in this browser. They are not uploaded to Kitharu, and the result stays on this device.

  • # subnet
  • # cidr