/18 subnet

Mask 255.255.192.0 · 16,382 usable hosts · 16,384 addresses

/18 at a glance
Subnet mask255.255.192.0
Wildcard mask0.0.63.255
Binary mask11111111.11111111.11000000.00000000
Network / host bits18 / 14
Total addresses16,384
Usable hosts16,382
Per /8 · /16 · /241,024 · 4 · –
Example192.168.10.77/18 → network 192.168.0.0, hosts 192.168.0.1 – 192.168.63.254, broadcast 192.168.63.255

Where /18 is used

A /18 is a less common size; it sits between /17 (32,768 addresses) and /19 (8,192 addresses).

Block boundaries: a /18 must start at a multiple of 16,384 addresses. Calculate any specific address in the subnet calculator.

Neighbouring prefixes

← /17 (twice as large) · /19 (half the size) →

Questions

How many hosts in a /18?
16,384 addresses, of which 16,382 are usable (the first is the network address and the last is broadcast).
What is the subnet mask for /18?
255.255.192.0. In binary: 11111111.11111111.11000000.00000000. The wildcard (inverse) mask is 0.0.63.255.