28.139.121.40/29
PublicClass A — /29 prefix — 6 usable hosts
Network address — the base address of the block (28.139.121.40). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 28.139.121.47 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 6 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.255.248 is the dotted-decimal equivalent of /29. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 28.139.121.40/29 |
| Network Address | 28.139.121.40 |
| Broadcast Address | 28.139.121.47 |
| Subnet Mask | 255.255.255.248 |
| Wildcard Mask | 0.0.0.7 |
| Prefix Length | /29 |
| IP Address Class | Class A |
| Total IP Addresses | 8 |
| Usable Host Addresses | 6 |
| First Usable IP | 28.139.121.41 |
| Last Usable IP | 28.139.121.46 |
| Network (Hex) | 0x1C8B7928 |
| Broadcast (Hex) | 0x1C8B792F |
| Address Type | Public / Globally Routable |
Binary Representation
The first 29 bits (1s in the mask) identify the network. The remaining 3 bits identify hosts within the network.
Split into Equal Subnets
Split 28.139.121.40/29 into 2 equal /30 subnets (2 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 28.139.121.40/30 | 28.139.121.40 | 28.139.121.41 | 28.139.121.42 | 28.139.121.43 | 2 |
| 2 | 28.139.121.44/30 | 28.139.121.44 | 28.139.121.45 | 28.139.121.46 | 28.139.121.47 | 2 |