172.0.0.0/6
PublicClass B — /6 prefix — 67,108,862 usable hosts
Network address — the base address of the block (172.0.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 175.255.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 67,108,862 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 252.0.0.0 is the dotted-decimal equivalent of /6. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 172.0.0.0/6 |
| Network Address | 172.0.0.0 |
| Broadcast Address | 175.255.255.255 |
| Subnet Mask | 252.0.0.0 |
| Wildcard Mask | 3.255.255.255 |
| Prefix Length | /6 |
| IP Address Class | Class B |
| Total IP Addresses | 67,108,864 |
| Usable Host Addresses | 67,108,862 |
| First Usable IP | 172.0.0.1 |
| Last Usable IP | 175.255.255.254 |
| Network (Hex) | 0xAC000000 |
| Broadcast (Hex) | 0xAFFFFFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 6 bits (1s in the mask) identify the network. The remaining 26 bits identify hosts within the network.
Subnet Breakdown — splitting into /7
This /6 block can be divided into 2 /7 subnets.
| CIDR | Network | Broadcast | First Usable | Last Usable | Hosts |
|---|---|---|---|---|---|
| 172.0.0.0/7 | 172.0.0.0 | 173.255.255.255 | 172.0.0.1 | 173.255.255.254 | 33,554,430 |
| 174.0.0.0/7 | 174.0.0.0 | 175.255.255.255 | 174.0.0.1 | 175.255.255.254 | 33,554,430 |