248.128.0.0/18
PublicClass E (Reserved) — /18 prefix — 16,382 usable hosts
Network address — the base address of the block (248.128.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 248.128.63.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 16,382 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.192.0 is the dotted-decimal equivalent of /18. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 248.128.0.0/18 |
| Network Address | 248.128.0.0 |
| Broadcast Address | 248.128.63.255 |
| Subnet Mask | 255.255.192.0 |
| Wildcard Mask | 0.0.63.255 |
| Prefix Length | /18 |
| IP Address Class | Class E (Reserved) |
| Total IP Addresses | 16,384 |
| Usable Host Addresses | 16,382 |
| First Usable IP | 248.128.0.1 |
| Last Usable IP | 248.128.63.254 |
| Network (Hex) | 0xF8800000 |
| Broadcast (Hex) | 0xF8803FFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 18 bits (1s in the mask) identify the network. The remaining 14 bits identify hosts within the network.
Split into Equal Subnets
Split 248.128.0.0/18 into 2 equal /19 subnets (8,190 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 248.128.0.0/19 | 248.128.0.0 | 248.128.0.1 | 248.128.31.254 | 248.128.31.255 | 8,190 |
| 2 | 248.128.32.0/19 | 248.128.32.0 | 248.128.32.1 | 248.128.63.254 | 248.128.63.255 | 8,190 |
Split 248.128.0.0/18 into 4 equal /20 subnets (4,094 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 248.128.0.0/20 | 248.128.0.0 | 248.128.0.1 | 248.128.15.254 | 248.128.15.255 | 4,094 |
| 2 | 248.128.16.0/20 | 248.128.16.0 | 248.128.16.1 | 248.128.31.254 | 248.128.31.255 | 4,094 |
| 3 | 248.128.32.0/20 | 248.128.32.0 | 248.128.32.1 | 248.128.47.254 | 248.128.47.255 | 4,094 |
| 4 | 248.128.48.0/20 | 248.128.48.0 | 248.128.48.1 | 248.128.63.254 | 248.128.63.255 | 4,094 |
Split 248.128.0.0/18 into 8 equal /21 subnets (2,046 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 248.128.0.0/21 | 248.128.0.0 | 248.128.0.1 | 248.128.7.254 | 248.128.7.255 | 2,046 |
| 2 | 248.128.8.0/21 | 248.128.8.0 | 248.128.8.1 | 248.128.15.254 | 248.128.15.255 | 2,046 |
| 3 | 248.128.16.0/21 | 248.128.16.0 | 248.128.16.1 | 248.128.23.254 | 248.128.23.255 | 2,046 |
| 4 | 248.128.24.0/21 | 248.128.24.0 | 248.128.24.1 | 248.128.31.254 | 248.128.31.255 | 2,046 |
| 5 | 248.128.32.0/21 | 248.128.32.0 | 248.128.32.1 | 248.128.39.254 | 248.128.39.255 | 2,046 |
| 6 | 248.128.40.0/21 | 248.128.40.0 | 248.128.40.1 | 248.128.47.254 | 248.128.47.255 | 2,046 |
| 7 | 248.128.48.0/21 | 248.128.48.0 | 248.128.48.1 | 248.128.55.254 | 248.128.55.255 | 2,046 |
| 8 | 248.128.56.0/21 | 248.128.56.0 | 248.128.56.1 | 248.128.63.254 | 248.128.63.255 | 2,046 |
Split 248.128.0.0/18 into 16 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 248.128.0.0/22 | 248.128.0.0 | 248.128.0.1 | 248.128.3.254 | 248.128.3.255 | 1,022 |
| 2 | 248.128.4.0/22 | 248.128.4.0 | 248.128.4.1 | 248.128.7.254 | 248.128.7.255 | 1,022 |
| 3 | 248.128.8.0/22 | 248.128.8.0 | 248.128.8.1 | 248.128.11.254 | 248.128.11.255 | 1,022 |
| 4 | 248.128.12.0/22 | 248.128.12.0 | 248.128.12.1 | 248.128.15.254 | 248.128.15.255 | 1,022 |
| 5 | 248.128.16.0/22 | 248.128.16.0 | 248.128.16.1 | 248.128.19.254 | 248.128.19.255 | 1,022 |
| 6 | 248.128.20.0/22 | 248.128.20.0 | 248.128.20.1 | 248.128.23.254 | 248.128.23.255 | 1,022 |
| 7 | 248.128.24.0/22 | 248.128.24.0 | 248.128.24.1 | 248.128.27.254 | 248.128.27.255 | 1,022 |
| 8 | 248.128.28.0/22 | 248.128.28.0 | 248.128.28.1 | 248.128.31.254 | 248.128.31.255 | 1,022 |
| 9 | 248.128.32.0/22 | 248.128.32.0 | 248.128.32.1 | 248.128.35.254 | 248.128.35.255 | 1,022 |
| 10 | 248.128.36.0/22 | 248.128.36.0 | 248.128.36.1 | 248.128.39.254 | 248.128.39.255 | 1,022 |
| 11 | 248.128.40.0/22 | 248.128.40.0 | 248.128.40.1 | 248.128.43.254 | 248.128.43.255 | 1,022 |
| 12 | 248.128.44.0/22 | 248.128.44.0 | 248.128.44.1 | 248.128.47.254 | 248.128.47.255 | 1,022 |
| 13 | 248.128.48.0/22 | 248.128.48.0 | 248.128.48.1 | 248.128.51.254 | 248.128.51.255 | 1,022 |
| 14 | 248.128.52.0/22 | 248.128.52.0 | 248.128.52.1 | 248.128.55.254 | 248.128.55.255 | 1,022 |
| 15 | 248.128.56.0/22 | 248.128.56.0 | 248.128.56.1 | 248.128.59.254 | 248.128.59.255 | 1,022 |
| 16 | 248.128.60.0/22 | 248.128.60.0 | 248.128.60.1 | 248.128.63.254 | 248.128.63.255 | 1,022 |