28.0.0.0/6
PublicClass A — /6 prefix — 67,108,862 usable hosts
Network address — the base address of the block (28.0.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 31.255.255.255 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 | 28.0.0.0/6 |
| Network Address | 28.0.0.0 |
| Broadcast Address | 31.255.255.255 |
| Subnet Mask | 252.0.0.0 |
| Wildcard Mask | 3.255.255.255 |
| Prefix Length | /6 |
| IP Address Class | Class A |
| Total IP Addresses | 67,108,864 |
| Usable Host Addresses | 67,108,862 |
| First Usable IP | 28.0.0.1 |
| Last Usable IP | 31.255.255.254 |
| Network (Hex) | 0x1C000000 |
| Broadcast (Hex) | 0x1FFFFFFF |
| 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.
Split into Equal Subnets
Split 28.0.0.0/6 into 2 equal /7 subnets (33,554,430 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.0.0.0/7 | 28.0.0.0 | 28.0.0.1 | 29.255.255.254 | 29.255.255.255 | 33,554,430 |
| 2 | 30.0.0.0/7 | 30.0.0.0 | 30.0.0.1 | 31.255.255.254 | 31.255.255.255 | 33,554,430 |
Split 28.0.0.0/6 into 4 equal /8 subnets (16,777,214 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.0.0.0/8 | 28.0.0.0 | 28.0.0.1 | 28.255.255.254 | 28.255.255.255 | 16,777,214 |
| 2 | 29.0.0.0/8 | 29.0.0.0 | 29.0.0.1 | 29.255.255.254 | 29.255.255.255 | 16,777,214 |
| 3 | 30.0.0.0/8 | 30.0.0.0 | 30.0.0.1 | 30.255.255.254 | 30.255.255.255 | 16,777,214 |
| 4 | 31.0.0.0/8 | 31.0.0.0 | 31.0.0.1 | 31.255.255.254 | 31.255.255.255 | 16,777,214 |
Split 28.0.0.0/6 into 8 equal /9 subnets (8,388,606 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.0.0.0/9 | 28.0.0.0 | 28.0.0.1 | 28.127.255.254 | 28.127.255.255 | 8,388,606 |
| 2 | 28.128.0.0/9 | 28.128.0.0 | 28.128.0.1 | 28.255.255.254 | 28.255.255.255 | 8,388,606 |
| 3 | 29.0.0.0/9 | 29.0.0.0 | 29.0.0.1 | 29.127.255.254 | 29.127.255.255 | 8,388,606 |
| 4 | 29.128.0.0/9 | 29.128.0.0 | 29.128.0.1 | 29.255.255.254 | 29.255.255.255 | 8,388,606 |
| 5 | 30.0.0.0/9 | 30.0.0.0 | 30.0.0.1 | 30.127.255.254 | 30.127.255.255 | 8,388,606 |
| 6 | 30.128.0.0/9 | 30.128.0.0 | 30.128.0.1 | 30.255.255.254 | 30.255.255.255 | 8,388,606 |
| 7 | 31.0.0.0/9 | 31.0.0.0 | 31.0.0.1 | 31.127.255.254 | 31.127.255.255 | 8,388,606 |
| 8 | 31.128.0.0/9 | 31.128.0.0 | 31.128.0.1 | 31.255.255.254 | 31.255.255.255 | 8,388,606 |
Split 28.0.0.0/6 into 16 equal /10 subnets (4,194,302 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.0.0.0/10 | 28.0.0.0 | 28.0.0.1 | 28.63.255.254 | 28.63.255.255 | 4,194,302 |
| 2 | 28.64.0.0/10 | 28.64.0.0 | 28.64.0.1 | 28.127.255.254 | 28.127.255.255 | 4,194,302 |
| 3 | 28.128.0.0/10 | 28.128.0.0 | 28.128.0.1 | 28.191.255.254 | 28.191.255.255 | 4,194,302 |
| 4 | 28.192.0.0/10 | 28.192.0.0 | 28.192.0.1 | 28.255.255.254 | 28.255.255.255 | 4,194,302 |
| 5 | 29.0.0.0/10 | 29.0.0.0 | 29.0.0.1 | 29.63.255.254 | 29.63.255.255 | 4,194,302 |
| 6 | 29.64.0.0/10 | 29.64.0.0 | 29.64.0.1 | 29.127.255.254 | 29.127.255.255 | 4,194,302 |
| 7 | 29.128.0.0/10 | 29.128.0.0 | 29.128.0.1 | 29.191.255.254 | 29.191.255.255 | 4,194,302 |
| 8 | 29.192.0.0/10 | 29.192.0.0 | 29.192.0.1 | 29.255.255.254 | 29.255.255.255 | 4,194,302 |
| 9 | 30.0.0.0/10 | 30.0.0.0 | 30.0.0.1 | 30.63.255.254 | 30.63.255.255 | 4,194,302 |
| 10 | 30.64.0.0/10 | 30.64.0.0 | 30.64.0.1 | 30.127.255.254 | 30.127.255.255 | 4,194,302 |
| 11 | 30.128.0.0/10 | 30.128.0.0 | 30.128.0.1 | 30.191.255.254 | 30.191.255.255 | 4,194,302 |
| 12 | 30.192.0.0/10 | 30.192.0.0 | 30.192.0.1 | 30.255.255.254 | 30.255.255.255 | 4,194,302 |
| 13 | 31.0.0.0/10 | 31.0.0.0 | 31.0.0.1 | 31.63.255.254 | 31.63.255.255 | 4,194,302 |
| 14 | 31.64.0.0/10 | 31.64.0.0 | 31.64.0.1 | 31.127.255.254 | 31.127.255.255 | 4,194,302 |
| 15 | 31.128.0.0/10 | 31.128.0.0 | 31.128.0.1 | 31.191.255.254 | 31.191.255.255 | 4,194,302 |
| 16 | 31.192.0.0/10 | 31.192.0.0 | 31.192.0.1 | 31.255.255.254 | 31.255.255.255 | 4,194,302 |