100.64.0.0/11
PublicClass A — /11 prefix — 2,097,150 usable hosts
Network address — the base address of the block (100.64.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 100.95.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 2,097,150 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.224.0.0 is the dotted-decimal equivalent of /11. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 100.64.0.0/11 |
| Network Address | 100.64.0.0 |
| Broadcast Address | 100.95.255.255 |
| Subnet Mask | 255.224.0.0 |
| Wildcard Mask | 0.31.255.255 |
| Prefix Length | /11 |
| IP Address Class | Class A |
| Total IP Addresses | 2,097,152 |
| Usable Host Addresses | 2,097,150 |
| First Usable IP | 100.64.0.1 |
| Last Usable IP | 100.95.255.254 |
| Network (Hex) | 0x64400000 |
| Broadcast (Hex) | 0x645FFFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 11 bits (1s in the mask) identify the network. The remaining 21 bits identify hosts within the network.
Subnet Breakdown — splitting into /12
This /11 block can be divided into 2 /12 subnets.
| CIDR | Network | Broadcast | First Usable | Last Usable | Hosts |
|---|---|---|---|---|---|
| 100.64.0.0/12 | 100.64.0.0 | 100.79.255.255 | 100.64.0.1 | 100.79.255.254 | 1,048,574 |
| 100.80.0.0/12 | 100.80.0.0 | 100.95.255.255 | 100.80.0.1 | 100.95.255.254 | 1,048,574 |