81.160.0.0/11
PublicClass A — /11 prefix — 2,097,150 usable hosts
Network address — the base address of the block (81.160.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 81.191.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 2,097,150 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.224.0.0 is the dotted-decimal equivalent of /11. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 81.160.0.0/11 |
| Network Address | 81.160.0.0 |
| Broadcast Address | 81.191.255.255 |
| Subnet Mask | 255.224.0.0 |
| Wildcard Mask | 0.31.255.255 |
| Prefix Length | /11 |
| IP Address Class | Class A |
| Total IP Addresses | 2,097,152 |
| Usable Host Addresses | 2,097,150 |
| First Usable IP | 81.160.0.1 |
| Last Usable IP | 81.191.255.254 |
| Network (Hex) | 0x51A00000 |
| Broadcast (Hex) | 0x51BFFFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 11 bits (1s in the mask) identify the network. The remaining 21 bits identify hosts within the network.
Split into Equal Subnets
Split 81.160.0.0/11 into 2 equal /12 subnets (1,048,574 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 81.160.0.0/12 | 81.160.0.0 | 81.160.0.1 | 81.175.255.254 | 81.175.255.255 | 1,048,574 |
| 2 | 81.176.0.0/12 | 81.176.0.0 | 81.176.0.1 | 81.191.255.254 | 81.191.255.255 | 1,048,574 |
Split 81.160.0.0/11 into 4 equal /13 subnets (524,286 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 81.160.0.0/13 | 81.160.0.0 | 81.160.0.1 | 81.167.255.254 | 81.167.255.255 | 524,286 |
| 2 | 81.168.0.0/13 | 81.168.0.0 | 81.168.0.1 | 81.175.255.254 | 81.175.255.255 | 524,286 |
| 3 | 81.176.0.0/13 | 81.176.0.0 | 81.176.0.1 | 81.183.255.254 | 81.183.255.255 | 524,286 |
| 4 | 81.184.0.0/13 | 81.184.0.0 | 81.184.0.1 | 81.191.255.254 | 81.191.255.255 | 524,286 |
Split 81.160.0.0/11 into 8 equal /14 subnets (262,142 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 81.160.0.0/14 | 81.160.0.0 | 81.160.0.1 | 81.163.255.254 | 81.163.255.255 | 262,142 |
| 2 | 81.164.0.0/14 | 81.164.0.0 | 81.164.0.1 | 81.167.255.254 | 81.167.255.255 | 262,142 |
| 3 | 81.168.0.0/14 | 81.168.0.0 | 81.168.0.1 | 81.171.255.254 | 81.171.255.255 | 262,142 |
| 4 | 81.172.0.0/14 | 81.172.0.0 | 81.172.0.1 | 81.175.255.254 | 81.175.255.255 | 262,142 |
| 5 | 81.176.0.0/14 | 81.176.0.0 | 81.176.0.1 | 81.179.255.254 | 81.179.255.255 | 262,142 |
| 6 | 81.180.0.0/14 | 81.180.0.0 | 81.180.0.1 | 81.183.255.254 | 81.183.255.255 | 262,142 |
| 7 | 81.184.0.0/14 | 81.184.0.0 | 81.184.0.1 | 81.187.255.254 | 81.187.255.255 | 262,142 |
| 8 | 81.188.0.0/14 | 81.188.0.0 | 81.188.0.1 | 81.191.255.254 | 81.191.255.255 | 262,142 |
Split 81.160.0.0/11 into 16 equal /15 subnets (131,070 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 81.160.0.0/15 | 81.160.0.0 | 81.160.0.1 | 81.161.255.254 | 81.161.255.255 | 131,070 |
| 2 | 81.162.0.0/15 | 81.162.0.0 | 81.162.0.1 | 81.163.255.254 | 81.163.255.255 | 131,070 |
| 3 | 81.164.0.0/15 | 81.164.0.0 | 81.164.0.1 | 81.165.255.254 | 81.165.255.255 | 131,070 |
| 4 | 81.166.0.0/15 | 81.166.0.0 | 81.166.0.1 | 81.167.255.254 | 81.167.255.255 | 131,070 |
| 5 | 81.168.0.0/15 | 81.168.0.0 | 81.168.0.1 | 81.169.255.254 | 81.169.255.255 | 131,070 |
| 6 | 81.170.0.0/15 | 81.170.0.0 | 81.170.0.1 | 81.171.255.254 | 81.171.255.255 | 131,070 |
| 7 | 81.172.0.0/15 | 81.172.0.0 | 81.172.0.1 | 81.173.255.254 | 81.173.255.255 | 131,070 |
| 8 | 81.174.0.0/15 | 81.174.0.0 | 81.174.0.1 | 81.175.255.254 | 81.175.255.255 | 131,070 |
| 9 | 81.176.0.0/15 | 81.176.0.0 | 81.176.0.1 | 81.177.255.254 | 81.177.255.255 | 131,070 |
| 10 | 81.178.0.0/15 | 81.178.0.0 | 81.178.0.1 | 81.179.255.254 | 81.179.255.255 | 131,070 |
| 11 | 81.180.0.0/15 | 81.180.0.0 | 81.180.0.1 | 81.181.255.254 | 81.181.255.255 | 131,070 |
| 12 | 81.182.0.0/15 | 81.182.0.0 | 81.182.0.1 | 81.183.255.254 | 81.183.255.255 | 131,070 |
| 13 | 81.184.0.0/15 | 81.184.0.0 | 81.184.0.1 | 81.185.255.254 | 81.185.255.255 | 131,070 |
| 14 | 81.186.0.0/15 | 81.186.0.0 | 81.186.0.1 | 81.187.255.254 | 81.187.255.255 | 131,070 |
| 15 | 81.188.0.0/15 | 81.188.0.0 | 81.188.0.1 | 81.189.255.254 | 81.189.255.255 | 131,070 |
| 16 | 81.190.0.0/15 | 81.190.0.0 | 81.190.0.1 | 81.191.255.254 | 81.191.255.255 | 131,070 |