Yurlie/16 Subnet Mask Reference
The subnet mask for prefix length /16 is 255.255.0.0. A large IPv4 subnet with 65.536 total addresses and 65.534 usable host addresses.
/16255.255.0.00.0.255.255FFFF000065.53416 / 32Binary Representation
11111111.11111111.00000000.0000000000000000.00000000.11111111.111111111-bits (network): 16 · 0-bits (host): 16 · Total: 32 bits
Common Uses for 255.255.0.0
- Class B network (legacy)
- Corporate LANs
- AWS default VPC (/16 is AWS best practice)
- 65,534 usable hosts
Frequently Asked Questions
What is the subnet mask for /16?
The subnet mask for prefix length /16 is 255.255.0.0. In hexadecimal it is 0xFFFF0000. The binary representation is 11111111.11111111.00000000.00000000.
What is the inverse (wildcard) mask of 255.255.0.0?
The wildcard mask (inverse mask) of 255.255.0.0 is 0.0.255.255. Wildcard masks are used in Cisco IOS ACLs and OSPF configurations to specify which bits of an IP address to match.
How many host IPs does 255.255.0.0 give?
With subnet mask 255.255.0.0 (/16), you get 65.536 total IPs, minus 2 reserved (network + broadcast) = 65.534 usable host addresses.
What CIDR prefix corresponds to 255.255.0.0?
The subnet mask 255.255.0.0 corresponds to CIDR prefix /16. This means 16 bits are used for the network portion and 16 bits for host addresses.
Complete Subnet Mask Reference /0–/32
| Prefix | Subnet Mask | Wildcard | Hex | Usable Hosts |
|---|---|---|---|---|
| /0 | 0.0.0.0 | 255.255.255.255 | 00000000 | 4.294.967.294 |
| /1 | 128.0.0.0 | 127.255.255.255 | 80000000 | 2.147.483.646 |
| /2 | 192.0.0.0 | 63.255.255.255 | C0000000 | 1.073.741.822 |
| /3 | 224.0.0.0 | 31.255.255.255 | E0000000 | 536.870.910 |
| /4 | 240.0.0.0 | 15.255.255.255 | F0000000 | 268.435.454 |
| /5 | 248.0.0.0 | 7.255.255.255 | F8000000 | 134.217.726 |
| /6 | 252.0.0.0 | 3.255.255.255 | FC000000 | 67.108.862 |
| /7 | 254.0.0.0 | 1.255.255.255 | FE000000 | 33.554.430 |
| /8 | 255.0.0.0 | 0.255.255.255 | FF000000 | 16.777.214 |
| /9 | 255.128.0.0 | 0.127.255.255 | FF800000 | 8.388.606 |
| /10 | 255.192.0.0 | 0.63.255.255 | FFC00000 | 4.194.302 |
| /11 | 255.224.0.0 | 0.31.255.255 | FFE00000 | 2.097.150 |
| /12 | 255.240.0.0 | 0.15.255.255 | FFF00000 | 1.048.574 |
| /13 | 255.248.0.0 | 0.7.255.255 | FFF80000 | 524.286 |
| /14 | 255.252.0.0 | 0.3.255.255 | FFFC0000 | 262.142 |
| /15 | 255.254.0.0 | 0.1.255.255 | FFFE0000 | 131.070 |
| /16 | 255.255.0.0 | 0.0.255.255 | FFFF0000 | 65.534 |
| /17 | 255.255.128.0 | 0.0.127.255 | FFFF8000 | 32.766 |
| /18 | 255.255.192.0 | 0.0.63.255 | FFFFC000 | 16.382 |
| /19 | 255.255.224.0 | 0.0.31.255 | FFFFE000 | 8.190 |
| /20 | 255.255.240.0 | 0.0.15.255 | FFFFF000 | 4.094 |
| /21 | 255.255.248.0 | 0.0.7.255 | FFFFF800 | 2.046 |
| /22 | 255.255.252.0 | 0.0.3.255 | FFFFFC00 | 1.022 |
| /23 | 255.255.254.0 | 0.0.1.255 | FFFFFE00 | 510 |
| /24 | 255.255.255.0 | 0.0.0.255 | FFFFFF00 | 254 |
| /25 | 255.255.255.128 | 0.0.0.127 | FFFFFF80 | 126 |
| /26 | 255.255.255.192 | 0.0.0.63 | FFFFFFC0 | 62 |
| /27 | 255.255.255.224 | 0.0.0.31 | FFFFFFE0 | 30 |
| /28 | 255.255.255.240 | 0.0.0.15 | FFFFFFF0 | 14 |
| /29 | 255.255.255.248 | 0.0.0.7 | FFFFFFF8 | 6 |
| /30 | 255.255.255.252 | 0.0.0.3 | FFFFFFFC | 2 |
| /31 | 255.255.255.254 | 0.0.0.1 | FFFFFFFE | 2 |
| /32 | 255.255.255.255 | 0.0.0.0 | FFFFFFFF | 1 |