64.0.0.0/4
PublicClass A — /4 prefix — 268,435,454 usable hosts
Network address — the base address of the block (64.0.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 79.255.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 268,435,454 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 240.0.0.0 is the dotted-decimal equivalent of /4. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 64.0.0.0/4 |
| Network Address | 64.0.0.0 |
| Broadcast Address | 79.255.255.255 |
| Subnet Mask | 240.0.0.0 |
| Wildcard Mask | 15.255.255.255 |
| Prefix Length | /4 |
| IP Address Class | Class A |
| Total IP Addresses | 268,435,456 |
| Usable Host Addresses | 268,435,454 |
| First Usable IP | 64.0.0.1 |
| Last Usable IP | 79.255.255.254 |
| Network (Hex) | 0x40000000 |
| Broadcast (Hex) | 0x4FFFFFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 4 bits (1s in the mask) identify the network. The remaining 28 bits identify hosts within the network.
Subnet Breakdown — splitting into /5
This /4 block can be divided into 2 /5 subnets.
| CIDR | Network | Broadcast | First Usable | Last Usable | Hosts |
|---|---|---|---|---|---|
| 64.0.0.0/5 | 64.0.0.0 | 71.255.255.255 | 64.0.0.1 | 71.255.255.254 | 134,217,726 |
| 72.0.0.0/5 | 72.0.0.0 | 79.255.255.255 | 72.0.0.1 | 79.255.255.254 | 134,217,726 |