Subnet Calculator.

Subnet Calculator.

Enter an IPv4 address and either a prefix (e.g. /24) or a subnet mask (e.g. 255.255.255.0). Click Calculate.

Quick examples: 10.0.0.5 /8, 172.16.5.4 255.255.252.0
Network
Broadcast
First host
Last host
Hosts per subnet
Prefix
Mask
Wildcard
Binary (IP / Mask)
Notes
  • /31 and /32 networks are handled specially: /31 has 0 usable hosts (RFC 3021) and /32 is a single-host route.
  • This tool only supports IPv4.