0.251.0.0/16
PublicClass A — /16 prefix — 65,534 usable hosts
Network address — the base address of the block (0.251.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 0.251.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 65,534 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.0.0 is the dotted-decimal equivalent of /16. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 0.251.0.0/16 |
| Network Address | 0.251.0.0 |
| Broadcast Address | 0.251.255.255 |
| Subnet Mask | 255.255.0.0 |
| Wildcard Mask | 0.0.255.255 |
| Prefix Length | /16 |
| IP Address Class | Class A |
| Total IP Addresses | 65,536 |
| Usable Host Addresses | 65,534 |
| First Usable IP | 0.251.0.1 |
| Last Usable IP | 0.251.255.254 |
| Network (Hex) | 0x00FB0000 |
| Broadcast (Hex) | 0x00FBFFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 16 bits (1s in the mask) identify the network. The remaining 16 bits identify hosts within the network.
Split into Equal Subnets
Split 0.251.0.0/16 into 2 equal /17 subnets (32,766 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 0.251.0.0/17 | 0.251.0.0 | 0.251.0.1 | 0.251.127.254 | 0.251.127.255 | 32,766 |
| 2 | 0.251.128.0/17 | 0.251.128.0 | 0.251.128.1 | 0.251.255.254 | 0.251.255.255 | 32,766 |
Split 0.251.0.0/16 into 4 equal /18 subnets (16,382 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 0.251.0.0/18 | 0.251.0.0 | 0.251.0.1 | 0.251.63.254 | 0.251.63.255 | 16,382 |
| 2 | 0.251.64.0/18 | 0.251.64.0 | 0.251.64.1 | 0.251.127.254 | 0.251.127.255 | 16,382 |
| 3 | 0.251.128.0/18 | 0.251.128.0 | 0.251.128.1 | 0.251.191.254 | 0.251.191.255 | 16,382 |
| 4 | 0.251.192.0/18 | 0.251.192.0 | 0.251.192.1 | 0.251.255.254 | 0.251.255.255 | 16,382 |
Split 0.251.0.0/16 into 8 equal /19 subnets (8,190 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 0.251.0.0/19 | 0.251.0.0 | 0.251.0.1 | 0.251.31.254 | 0.251.31.255 | 8,190 |
| 2 | 0.251.32.0/19 | 0.251.32.0 | 0.251.32.1 | 0.251.63.254 | 0.251.63.255 | 8,190 |
| 3 | 0.251.64.0/19 | 0.251.64.0 | 0.251.64.1 | 0.251.95.254 | 0.251.95.255 | 8,190 |
| 4 | 0.251.96.0/19 | 0.251.96.0 | 0.251.96.1 | 0.251.127.254 | 0.251.127.255 | 8,190 |
| 5 | 0.251.128.0/19 | 0.251.128.0 | 0.251.128.1 | 0.251.159.254 | 0.251.159.255 | 8,190 |
| 6 | 0.251.160.0/19 | 0.251.160.0 | 0.251.160.1 | 0.251.191.254 | 0.251.191.255 | 8,190 |
| 7 | 0.251.192.0/19 | 0.251.192.0 | 0.251.192.1 | 0.251.223.254 | 0.251.223.255 | 8,190 |
| 8 | 0.251.224.0/19 | 0.251.224.0 | 0.251.224.1 | 0.251.255.254 | 0.251.255.255 | 8,190 |
Split 0.251.0.0/16 into 16 equal /20 subnets (4,094 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 0.251.0.0/20 | 0.251.0.0 | 0.251.0.1 | 0.251.15.254 | 0.251.15.255 | 4,094 |
| 2 | 0.251.16.0/20 | 0.251.16.0 | 0.251.16.1 | 0.251.31.254 | 0.251.31.255 | 4,094 |
| 3 | 0.251.32.0/20 | 0.251.32.0 | 0.251.32.1 | 0.251.47.254 | 0.251.47.255 | 4,094 |
| 4 | 0.251.48.0/20 | 0.251.48.0 | 0.251.48.1 | 0.251.63.254 | 0.251.63.255 | 4,094 |
| 5 | 0.251.64.0/20 | 0.251.64.0 | 0.251.64.1 | 0.251.79.254 | 0.251.79.255 | 4,094 |
| 6 | 0.251.80.0/20 | 0.251.80.0 | 0.251.80.1 | 0.251.95.254 | 0.251.95.255 | 4,094 |
| 7 | 0.251.96.0/20 | 0.251.96.0 | 0.251.96.1 | 0.251.111.254 | 0.251.111.255 | 4,094 |
| 8 | 0.251.112.0/20 | 0.251.112.0 | 0.251.112.1 | 0.251.127.254 | 0.251.127.255 | 4,094 |
| 9 | 0.251.128.0/20 | 0.251.128.0 | 0.251.128.1 | 0.251.143.254 | 0.251.143.255 | 4,094 |
| 10 | 0.251.144.0/20 | 0.251.144.0 | 0.251.144.1 | 0.251.159.254 | 0.251.159.255 | 4,094 |
| 11 | 0.251.160.0/20 | 0.251.160.0 | 0.251.160.1 | 0.251.175.254 | 0.251.175.255 | 4,094 |
| 12 | 0.251.176.0/20 | 0.251.176.0 | 0.251.176.1 | 0.251.191.254 | 0.251.191.255 | 4,094 |
| 13 | 0.251.192.0/20 | 0.251.192.0 | 0.251.192.1 | 0.251.207.254 | 0.251.207.255 | 4,094 |
| 14 | 0.251.208.0/20 | 0.251.208.0 | 0.251.208.1 | 0.251.223.254 | 0.251.223.255 | 4,094 |
| 15 | 0.251.224.0/20 | 0.251.224.0 | 0.251.224.1 | 0.251.239.254 | 0.251.239.255 | 4,094 |
| 16 | 0.251.240.0/20 | 0.251.240.0 | 0.251.240.1 | 0.251.255.254 | 0.251.255.255 | 4,094 |