100.97.80.0/20
PublicClass A — /20 prefix — 4,094 usable hosts
Network address — the base address of the block (100.97.80.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 100.97.95.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 4,094 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.240.0 is the dotted-decimal equivalent of /20. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 100.97.80.0/20 |
| Network Address | 100.97.80.0 |
| Broadcast Address | 100.97.95.255 |
| Subnet Mask | 255.255.240.0 |
| Wildcard Mask | 0.0.15.255 |
| Prefix Length | /20 |
| IP Address Class | Class A |
| Total IP Addresses | 4,096 |
| Usable Host Addresses | 4,094 |
| First Usable IP | 100.97.80.1 |
| Last Usable IP | 100.97.95.254 |
| Network (Hex) | 0x64615000 |
| Broadcast (Hex) | 0x64615FFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 20 bits (1s in the mask) identify the network. The remaining 12 bits identify hosts within the network.
Split into Equal Subnets
Split 100.97.80.0/20 into 2 equal /21 subnets (2,046 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 100.97.80.0/21 | 100.97.80.0 | 100.97.80.1 | 100.97.87.254 | 100.97.87.255 | 2,046 |
| 2 | 100.97.88.0/21 | 100.97.88.0 | 100.97.88.1 | 100.97.95.254 | 100.97.95.255 | 2,046 |
Split 100.97.80.0/20 into 4 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 100.97.80.0/22 | 100.97.80.0 | 100.97.80.1 | 100.97.83.254 | 100.97.83.255 | 1,022 |
| 2 | 100.97.84.0/22 | 100.97.84.0 | 100.97.84.1 | 100.97.87.254 | 100.97.87.255 | 1,022 |
| 3 | 100.97.88.0/22 | 100.97.88.0 | 100.97.88.1 | 100.97.91.254 | 100.97.91.255 | 1,022 |
| 4 | 100.97.92.0/22 | 100.97.92.0 | 100.97.92.1 | 100.97.95.254 | 100.97.95.255 | 1,022 |
Split 100.97.80.0/20 into 8 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 100.97.80.0/23 | 100.97.80.0 | 100.97.80.1 | 100.97.81.254 | 100.97.81.255 | 510 |
| 2 | 100.97.82.0/23 | 100.97.82.0 | 100.97.82.1 | 100.97.83.254 | 100.97.83.255 | 510 |
| 3 | 100.97.84.0/23 | 100.97.84.0 | 100.97.84.1 | 100.97.85.254 | 100.97.85.255 | 510 |
| 4 | 100.97.86.0/23 | 100.97.86.0 | 100.97.86.1 | 100.97.87.254 | 100.97.87.255 | 510 |
| 5 | 100.97.88.0/23 | 100.97.88.0 | 100.97.88.1 | 100.97.89.254 | 100.97.89.255 | 510 |
| 6 | 100.97.90.0/23 | 100.97.90.0 | 100.97.90.1 | 100.97.91.254 | 100.97.91.255 | 510 |
| 7 | 100.97.92.0/23 | 100.97.92.0 | 100.97.92.1 | 100.97.93.254 | 100.97.93.255 | 510 |
| 8 | 100.97.94.0/23 | 100.97.94.0 | 100.97.94.1 | 100.97.95.254 | 100.97.95.255 | 510 |
Split 100.97.80.0/20 into 16 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 100.97.80.0/24 | 100.97.80.0 | 100.97.80.1 | 100.97.80.254 | 100.97.80.255 | 254 |
| 2 | 100.97.81.0/24 | 100.97.81.0 | 100.97.81.1 | 100.97.81.254 | 100.97.81.255 | 254 |
| 3 | 100.97.82.0/24 | 100.97.82.0 | 100.97.82.1 | 100.97.82.254 | 100.97.82.255 | 254 |
| 4 | 100.97.83.0/24 | 100.97.83.0 | 100.97.83.1 | 100.97.83.254 | 100.97.83.255 | 254 |
| 5 | 100.97.84.0/24 | 100.97.84.0 | 100.97.84.1 | 100.97.84.254 | 100.97.84.255 | 254 |
| 6 | 100.97.85.0/24 | 100.97.85.0 | 100.97.85.1 | 100.97.85.254 | 100.97.85.255 | 254 |
| 7 | 100.97.86.0/24 | 100.97.86.0 | 100.97.86.1 | 100.97.86.254 | 100.97.86.255 | 254 |
| 8 | 100.97.87.0/24 | 100.97.87.0 | 100.97.87.1 | 100.97.87.254 | 100.97.87.255 | 254 |
| 9 | 100.97.88.0/24 | 100.97.88.0 | 100.97.88.1 | 100.97.88.254 | 100.97.88.255 | 254 |
| 10 | 100.97.89.0/24 | 100.97.89.0 | 100.97.89.1 | 100.97.89.254 | 100.97.89.255 | 254 |
| 11 | 100.97.90.0/24 | 100.97.90.0 | 100.97.90.1 | 100.97.90.254 | 100.97.90.255 | 254 |
| 12 | 100.97.91.0/24 | 100.97.91.0 | 100.97.91.1 | 100.97.91.254 | 100.97.91.255 | 254 |
| 13 | 100.97.92.0/24 | 100.97.92.0 | 100.97.92.1 | 100.97.92.254 | 100.97.92.255 | 254 |
| 14 | 100.97.93.0/24 | 100.97.93.0 | 100.97.93.1 | 100.97.93.254 | 100.97.93.255 | 254 |
| 15 | 100.97.94.0/24 | 100.97.94.0 | 100.97.94.1 | 100.97.94.254 | 100.97.94.255 | 254 |
| 16 | 100.97.95.0/24 | 100.97.95.0 | 100.97.95.1 | 100.97.95.254 | 100.97.95.255 | 254 |