18.64.0.0/19
PublicClass A — /19 prefix — 8,190 usable hosts
Network address — the base address of the block (18.64.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 18.64.31.255 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 | 18.64.0.0/19 |
| Network Address | 18.64.0.0 |
| Broadcast Address | 18.64.31.255 |
| Subnet Mask | 255.255.224.0 |
| Wildcard Mask | 0.0.31.255 |
| Prefix Length | /19 |
| IP Address Class | Class A |
| Total IP Addresses | 8,192 |
| Usable Host Addresses | 8,190 |
| First Usable IP | 18.64.0.1 |
| Last Usable IP | 18.64.31.254 |
| Network (Hex) | 0x12400000 |
| Broadcast (Hex) | 0x12401FFF |
| 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 18.64.0.0/19 into 2 equal /20 subnets (4,094 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 18.64.0.0/20 | 18.64.0.0 | 18.64.0.1 | 18.64.15.254 | 18.64.15.255 | 4,094 |
| 2 | 18.64.16.0/20 | 18.64.16.0 | 18.64.16.1 | 18.64.31.254 | 18.64.31.255 | 4,094 |
Split 18.64.0.0/19 into 4 equal /21 subnets (2,046 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 18.64.0.0/21 | 18.64.0.0 | 18.64.0.1 | 18.64.7.254 | 18.64.7.255 | 2,046 |
| 2 | 18.64.8.0/21 | 18.64.8.0 | 18.64.8.1 | 18.64.15.254 | 18.64.15.255 | 2,046 |
| 3 | 18.64.16.0/21 | 18.64.16.0 | 18.64.16.1 | 18.64.23.254 | 18.64.23.255 | 2,046 |
| 4 | 18.64.24.0/21 | 18.64.24.0 | 18.64.24.1 | 18.64.31.254 | 18.64.31.255 | 2,046 |
Split 18.64.0.0/19 into 8 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 18.64.0.0/22 | 18.64.0.0 | 18.64.0.1 | 18.64.3.254 | 18.64.3.255 | 1,022 |
| 2 | 18.64.4.0/22 | 18.64.4.0 | 18.64.4.1 | 18.64.7.254 | 18.64.7.255 | 1,022 |
| 3 | 18.64.8.0/22 | 18.64.8.0 | 18.64.8.1 | 18.64.11.254 | 18.64.11.255 | 1,022 |
| 4 | 18.64.12.0/22 | 18.64.12.0 | 18.64.12.1 | 18.64.15.254 | 18.64.15.255 | 1,022 |
| 5 | 18.64.16.0/22 | 18.64.16.0 | 18.64.16.1 | 18.64.19.254 | 18.64.19.255 | 1,022 |
| 6 | 18.64.20.0/22 | 18.64.20.0 | 18.64.20.1 | 18.64.23.254 | 18.64.23.255 | 1,022 |
| 7 | 18.64.24.0/22 | 18.64.24.0 | 18.64.24.1 | 18.64.27.254 | 18.64.27.255 | 1,022 |
| 8 | 18.64.28.0/22 | 18.64.28.0 | 18.64.28.1 | 18.64.31.254 | 18.64.31.255 | 1,022 |
Split 18.64.0.0/19 into 16 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 18.64.0.0/23 | 18.64.0.0 | 18.64.0.1 | 18.64.1.254 | 18.64.1.255 | 510 |
| 2 | 18.64.2.0/23 | 18.64.2.0 | 18.64.2.1 | 18.64.3.254 | 18.64.3.255 | 510 |
| 3 | 18.64.4.0/23 | 18.64.4.0 | 18.64.4.1 | 18.64.5.254 | 18.64.5.255 | 510 |
| 4 | 18.64.6.0/23 | 18.64.6.0 | 18.64.6.1 | 18.64.7.254 | 18.64.7.255 | 510 |
| 5 | 18.64.8.0/23 | 18.64.8.0 | 18.64.8.1 | 18.64.9.254 | 18.64.9.255 | 510 |
| 6 | 18.64.10.0/23 | 18.64.10.0 | 18.64.10.1 | 18.64.11.254 | 18.64.11.255 | 510 |
| 7 | 18.64.12.0/23 | 18.64.12.0 | 18.64.12.1 | 18.64.13.254 | 18.64.13.255 | 510 |
| 8 | 18.64.14.0/23 | 18.64.14.0 | 18.64.14.1 | 18.64.15.254 | 18.64.15.255 | 510 |
| 9 | 18.64.16.0/23 | 18.64.16.0 | 18.64.16.1 | 18.64.17.254 | 18.64.17.255 | 510 |
| 10 | 18.64.18.0/23 | 18.64.18.0 | 18.64.18.1 | 18.64.19.254 | 18.64.19.255 | 510 |
| 11 | 18.64.20.0/23 | 18.64.20.0 | 18.64.20.1 | 18.64.21.254 | 18.64.21.255 | 510 |
| 12 | 18.64.22.0/23 | 18.64.22.0 | 18.64.22.1 | 18.64.23.254 | 18.64.23.255 | 510 |
| 13 | 18.64.24.0/23 | 18.64.24.0 | 18.64.24.1 | 18.64.25.254 | 18.64.25.255 | 510 |
| 14 | 18.64.26.0/23 | 18.64.26.0 | 18.64.26.1 | 18.64.27.254 | 18.64.27.255 | 510 |
| 15 | 18.64.28.0/23 | 18.64.28.0 | 18.64.28.1 | 18.64.29.254 | 18.64.29.255 | 510 |
| 16 | 18.64.30.0/23 | 18.64.30.0 | 18.64.30.1 | 18.64.31.254 | 18.64.31.255 | 510 |