251.72.224.0/19
PublicClass E (Reserved) — /19 prefix — 8,190 usable hosts
Network address — the base address of the block (251.72.224.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 251.72.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 8,190 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.224.0 is the dotted-decimal equivalent of /19. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 251.72.224.0/19 |
| Network Address | 251.72.224.0 |
| Broadcast Address | 251.72.255.255 |
| Subnet Mask | 255.255.224.0 |
| Wildcard Mask | 0.0.31.255 |
| Prefix Length | /19 |
| IP Address Class | Class E (Reserved) |
| Total IP Addresses | 8,192 |
| Usable Host Addresses | 8,190 |
| First Usable IP | 251.72.224.1 |
| Last Usable IP | 251.72.255.254 |
| Network (Hex) | 0xFB48E000 |
| Broadcast (Hex) | 0xFB48FFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 19 bits (1s in the mask) identify the network. The remaining 13 bits identify hosts within the network.
Split into Equal Subnets
Split 251.72.224.0/19 into 2 equal /20 subnets (4,094 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 251.72.224.0/20 | 251.72.224.0 | 251.72.224.1 | 251.72.239.254 | 251.72.239.255 | 4,094 |
| 2 | 251.72.240.0/20 | 251.72.240.0 | 251.72.240.1 | 251.72.255.254 | 251.72.255.255 | 4,094 |
Split 251.72.224.0/19 into 4 equal /21 subnets (2,046 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 251.72.224.0/21 | 251.72.224.0 | 251.72.224.1 | 251.72.231.254 | 251.72.231.255 | 2,046 |
| 2 | 251.72.232.0/21 | 251.72.232.0 | 251.72.232.1 | 251.72.239.254 | 251.72.239.255 | 2,046 |
| 3 | 251.72.240.0/21 | 251.72.240.0 | 251.72.240.1 | 251.72.247.254 | 251.72.247.255 | 2,046 |
| 4 | 251.72.248.0/21 | 251.72.248.0 | 251.72.248.1 | 251.72.255.254 | 251.72.255.255 | 2,046 |
Split 251.72.224.0/19 into 8 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 251.72.224.0/22 | 251.72.224.0 | 251.72.224.1 | 251.72.227.254 | 251.72.227.255 | 1,022 |
| 2 | 251.72.228.0/22 | 251.72.228.0 | 251.72.228.1 | 251.72.231.254 | 251.72.231.255 | 1,022 |
| 3 | 251.72.232.0/22 | 251.72.232.0 | 251.72.232.1 | 251.72.235.254 | 251.72.235.255 | 1,022 |
| 4 | 251.72.236.0/22 | 251.72.236.0 | 251.72.236.1 | 251.72.239.254 | 251.72.239.255 | 1,022 |
| 5 | 251.72.240.0/22 | 251.72.240.0 | 251.72.240.1 | 251.72.243.254 | 251.72.243.255 | 1,022 |
| 6 | 251.72.244.0/22 | 251.72.244.0 | 251.72.244.1 | 251.72.247.254 | 251.72.247.255 | 1,022 |
| 7 | 251.72.248.0/22 | 251.72.248.0 | 251.72.248.1 | 251.72.251.254 | 251.72.251.255 | 1,022 |
| 8 | 251.72.252.0/22 | 251.72.252.0 | 251.72.252.1 | 251.72.255.254 | 251.72.255.255 | 1,022 |
Split 251.72.224.0/19 into 16 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 251.72.224.0/23 | 251.72.224.0 | 251.72.224.1 | 251.72.225.254 | 251.72.225.255 | 510 |
| 2 | 251.72.226.0/23 | 251.72.226.0 | 251.72.226.1 | 251.72.227.254 | 251.72.227.255 | 510 |
| 3 | 251.72.228.0/23 | 251.72.228.0 | 251.72.228.1 | 251.72.229.254 | 251.72.229.255 | 510 |
| 4 | 251.72.230.0/23 | 251.72.230.0 | 251.72.230.1 | 251.72.231.254 | 251.72.231.255 | 510 |
| 5 | 251.72.232.0/23 | 251.72.232.0 | 251.72.232.1 | 251.72.233.254 | 251.72.233.255 | 510 |
| 6 | 251.72.234.0/23 | 251.72.234.0 | 251.72.234.1 | 251.72.235.254 | 251.72.235.255 | 510 |
| 7 | 251.72.236.0/23 | 251.72.236.0 | 251.72.236.1 | 251.72.237.254 | 251.72.237.255 | 510 |
| 8 | 251.72.238.0/23 | 251.72.238.0 | 251.72.238.1 | 251.72.239.254 | 251.72.239.255 | 510 |
| 9 | 251.72.240.0/23 | 251.72.240.0 | 251.72.240.1 | 251.72.241.254 | 251.72.241.255 | 510 |
| 10 | 251.72.242.0/23 | 251.72.242.0 | 251.72.242.1 | 251.72.243.254 | 251.72.243.255 | 510 |
| 11 | 251.72.244.0/23 | 251.72.244.0 | 251.72.244.1 | 251.72.245.254 | 251.72.245.255 | 510 |
| 12 | 251.72.246.0/23 | 251.72.246.0 | 251.72.246.1 | 251.72.247.254 | 251.72.247.255 | 510 |
| 13 | 251.72.248.0/23 | 251.72.248.0 | 251.72.248.1 | 251.72.249.254 | 251.72.249.255 | 510 |
| 14 | 251.72.250.0/23 | 251.72.250.0 | 251.72.250.1 | 251.72.251.254 | 251.72.251.255 | 510 |
| 15 | 251.72.252.0/23 | 251.72.252.0 | 251.72.252.1 | 251.72.253.254 | 251.72.253.255 | 510 |
| 16 | 251.72.254.0/23 | 251.72.254.0 | 251.72.254.1 | 251.72.255.254 | 251.72.255.255 | 510 |