IPv4 Subnet Calculator

Network address, broadcast, host range, wildcard mask and binary breakdown for any IPv4 CIDR block.

Accepts 10.0.0.5/26, 10.0.0.5 255.255.255.192, or a bare IP.

Results for 198.51.102.0/23

198.51.102.0/23 is the network in CIDR notation · Public
Network address
198.51.102.0
Broadcast address
198.51.103.255
Subnet mask
255.255.254.0
Wildcard mask
0.0.1.255
Total addresses
512
Usable hosts
510 (excludes network & broadcast)
First usable host
198.51.102.1
Last usable host
198.51.103.254
CIDR notation
198.51.102.0/23
IP type
Public

How the bits line up

Octets (binary)
IP address11000110001100110110011000000000
Subnet mask11111111111111111111111000000000
Network11000110001100110110011000000000
Broadcast11000110001100110110011111111111

The mask's 23 leading ones select the network portion; the remaining 9 bits are available for hosts.

Keep exploring

See every fact about the /23 subnet mask, plan multiple subnets with the VLSM calculator, or convert ranges on the range-to-CIDR tool.