/23 subnet
Mask 255.255.254.0 · 510 usable hosts · 512 addresses
| Subnet mask | 255.255.254.0 |
|---|---|
| Wildcard mask | 0.0.1.255 |
| Binary mask | 11111111.11111111.11111110.00000000 |
| Network / host bits | 23 / 9 |
| Total addresses | 512 |
| Usable hosts | 510 |
| Per /8 · /16 · /24 | 32,768 · 128 · – |
| Example | 192.168.10.77/23 → network 192.168.10.0, hosts 192.168.10.1 – 192.168.11.254, broadcast 192.168.11.255 |
Where /23 is used
Two adjacent /24s; a larger home or office LAN.
Block boundaries: a /23 must start at a multiple of 512 addresses. Calculate any specific address in the subnet calculator.
Neighbouring prefixes
Questions
How many hosts in a /23?
512 addresses, of which 510 are usable (the first is the network address and the last is broadcast).
What is the subnet mask for /23?
255.255.254.0. In binary: 11111111.11111111.11111110.00000000. The wildcard (inverse) mask is 0.0.1.255.