28.9.12.0/25
PublicClass A — /25 prefix — 126 usable hosts
Network address — the base address of the block (28.9.12.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 28.9.12.127 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 126 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.255.128 is the dotted-decimal equivalent of /25. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 28.9.12.0/25 |
| Network Address | 28.9.12.0 |
| Broadcast Address | 28.9.12.127 |
| Subnet Mask | 255.255.255.128 |
| Wildcard Mask | 0.0.0.127 |
| Prefix Length | /25 |
| IP Address Class | Class A |
| Total IP Addresses | 128 |
| Usable Host Addresses | 126 |
| First Usable IP | 28.9.12.1 |
| Last Usable IP | 28.9.12.126 |
| Network (Hex) | 0x1C090C00 |
| Broadcast (Hex) | 0x1C090C7F |
| Address Type | Public / Globally Routable |
Binary Representation
The first 25 bits (1s in the mask) identify the network. The remaining 7 bits identify hosts within the network.
Split into Equal Subnets
Split 28.9.12.0/25 into 2 equal /26 subnets (62 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.9.12.0/26 | 28.9.12.0 | 28.9.12.1 | 28.9.12.62 | 28.9.12.63 | 62 |
| 2 | 28.9.12.64/26 | 28.9.12.64 | 28.9.12.65 | 28.9.12.126 | 28.9.12.127 | 62 |
Split 28.9.12.0/25 into 4 equal /27 subnets (30 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.9.12.0/27 | 28.9.12.0 | 28.9.12.1 | 28.9.12.30 | 28.9.12.31 | 30 |
| 2 | 28.9.12.32/27 | 28.9.12.32 | 28.9.12.33 | 28.9.12.62 | 28.9.12.63 | 30 |
| 3 | 28.9.12.64/27 | 28.9.12.64 | 28.9.12.65 | 28.9.12.94 | 28.9.12.95 | 30 |
| 4 | 28.9.12.96/27 | 28.9.12.96 | 28.9.12.97 | 28.9.12.126 | 28.9.12.127 | 30 |
Split 28.9.12.0/25 into 8 equal /28 subnets (14 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.9.12.0/28 | 28.9.12.0 | 28.9.12.1 | 28.9.12.14 | 28.9.12.15 | 14 |
| 2 | 28.9.12.16/28 | 28.9.12.16 | 28.9.12.17 | 28.9.12.30 | 28.9.12.31 | 14 |
| 3 | 28.9.12.32/28 | 28.9.12.32 | 28.9.12.33 | 28.9.12.46 | 28.9.12.47 | 14 |
| 4 | 28.9.12.48/28 | 28.9.12.48 | 28.9.12.49 | 28.9.12.62 | 28.9.12.63 | 14 |
| 5 | 28.9.12.64/28 | 28.9.12.64 | 28.9.12.65 | 28.9.12.78 | 28.9.12.79 | 14 |
| 6 | 28.9.12.80/28 | 28.9.12.80 | 28.9.12.81 | 28.9.12.94 | 28.9.12.95 | 14 |
| 7 | 28.9.12.96/28 | 28.9.12.96 | 28.9.12.97 | 28.9.12.110 | 28.9.12.111 | 14 |
| 8 | 28.9.12.112/28 | 28.9.12.112 | 28.9.12.113 | 28.9.12.126 | 28.9.12.127 | 14 |
Split 28.9.12.0/25 into 16 equal /29 subnets (6 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.9.12.0/29 | 28.9.12.0 | 28.9.12.1 | 28.9.12.6 | 28.9.12.7 | 6 |
| 2 | 28.9.12.8/29 | 28.9.12.8 | 28.9.12.9 | 28.9.12.14 | 28.9.12.15 | 6 |
| 3 | 28.9.12.16/29 | 28.9.12.16 | 28.9.12.17 | 28.9.12.22 | 28.9.12.23 | 6 |
| 4 | 28.9.12.24/29 | 28.9.12.24 | 28.9.12.25 | 28.9.12.30 | 28.9.12.31 | 6 |
| 5 | 28.9.12.32/29 | 28.9.12.32 | 28.9.12.33 | 28.9.12.38 | 28.9.12.39 | 6 |
| 6 | 28.9.12.40/29 | 28.9.12.40 | 28.9.12.41 | 28.9.12.46 | 28.9.12.47 | 6 |
| 7 | 28.9.12.48/29 | 28.9.12.48 | 28.9.12.49 | 28.9.12.54 | 28.9.12.55 | 6 |
| 8 | 28.9.12.56/29 | 28.9.12.56 | 28.9.12.57 | 28.9.12.62 | 28.9.12.63 | 6 |
| 9 | 28.9.12.64/29 | 28.9.12.64 | 28.9.12.65 | 28.9.12.70 | 28.9.12.71 | 6 |
| 10 | 28.9.12.72/29 | 28.9.12.72 | 28.9.12.73 | 28.9.12.78 | 28.9.12.79 | 6 |
| 11 | 28.9.12.80/29 | 28.9.12.80 | 28.9.12.81 | 28.9.12.86 | 28.9.12.87 | 6 |
| 12 | 28.9.12.88/29 | 28.9.12.88 | 28.9.12.89 | 28.9.12.94 | 28.9.12.95 | 6 |
| 13 | 28.9.12.96/29 | 28.9.12.96 | 28.9.12.97 | 28.9.12.102 | 28.9.12.103 | 6 |
| 14 | 28.9.12.104/29 | 28.9.12.104 | 28.9.12.105 | 28.9.12.110 | 28.9.12.111 | 6 |
| 15 | 28.9.12.112/29 | 28.9.12.112 | 28.9.12.113 | 28.9.12.118 | 28.9.12.119 | 6 |
| 16 | 28.9.12.120/29 | 28.9.12.120 | 28.9.12.121 | 28.9.12.126 | 28.9.12.127 | 6 |
IP Address Sample
Showing first 16 of 128 total IPs.