A /18 uses the mask 255.255.192.0, so the third octet steps in blocks of 64: 0, 64, 128 and 192. That makes it one of the easier sizes to subnet by hand. At 16,382 usable hosts it suits a campus or data-center allocation that gets divided further, not a single LAN.
Facts
- Prefix
- /18
- Subnet mask
- 255.255.192.0
- Wildcard mask
- 0.0.63.255
- Binary mask
- 11111111.11111111.11000000.00000000
- Total addresses
- 16,384
- Usable hosts
- 16,382
- Example range
- 192.168.0.0/18: 192.168.0.0 – 192.168.63.255
- Typical use
- Large enterprise networks.
Try it
Try: , ,
- CIDR block
- 192.168.0.0/18
- IP range
- 192.168.0.0 – 192.168.63.255
- Addresses
- 16,384
- Usable hosts
- 16,382
- Subnet mask
- 255.255.192.0
- Wildcard mask
- 0.0.63.255
Frequently asked questions
How many hosts are in a /18?
A /18 has 16,384 addresses. Subtracting the network and broadcast addresses leaves 16,382 usable hosts.
What is the subnet mask for /18?
/18 is 255.255.192.0 (wildcard mask 0.0.63.255). In binary that’s 18 ones followed by 14 zeros.