/16 Subnet Mask: 255.255.0.0 (65,534 Usable Hosts)

A /16 subnet mask is 255.255.0.0, with 65,536 addresses and 65,534 usable hosts.

CIDR prefix	/16
Subnet mask	255.255.0.0
Subnet mask (binary)	`11111111.11111111.00000000.00000000`
Wildcard mask	0.0.255.255
Network bits / host bits	16 / 16
Total addresses	65,536
Usable hosts	65,534
/16 subnets in a /8	256

The mask ends exactly on an octet boundary, so every address in a /16 block shares its first 2 octets. The size of the classic Class B block and of the 192.168.0.0/16 private range. Commonly split into 256 /24 subnets, one per site or VLAN.

Try it with an address

Example /16 subnets in 192.168.0.0/16

Network	First usable host	Last usable host	Broadcast
192.168.0.0/16	192.168.0.1	192.168.255.254	192.168.255.255

Frequently asked questions

What is the subnet mask for /16?

A /16 subnet mask is 255.255.0.0. In binary that is 11111111.11111111.00000000.00000000: 16 network bits followed by 16 host bits. The wildcard mask is 0.0.255.255.

How many usable hosts are in a /16?

A /16 holds 65,536 addresses in total. Subtracting the network and broadcast addresses leaves 65,534 usable hosts.

How many /16 subnets fit in a /8?

A /8 divides into 256 subnets of size /16, because each extra mask bit doubles the number of subnets.

Other prefix lengths

Calculate this over HTTP: curl https://networkcalc.com/api/ip/192.168.1.0/16. See the Subnet Calculator API.