191.252.24.0/21
PublicClass B — /21 prefix — 2,046 usable hosts
Network address — the base address of the block (191.252.24.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 191.252.31.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 2,046 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.248.0 is the dotted-decimal equivalent of /21. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 191.252.24.0/21 |
| Network Address | 191.252.24.0 |
| Broadcast Address | 191.252.31.255 |
| Subnet Mask | 255.255.248.0 |
| Wildcard Mask | 0.0.7.255 |
| Prefix Length | /21 |
| IP Address Class | Class B |
| Total IP Addresses | 2,048 |
| Usable Host Addresses | 2,046 |
| First Usable IP | 191.252.24.1 |
| Last Usable IP | 191.252.31.254 |
| Network (Hex) | 0xBFFC1800 |
| Broadcast (Hex) | 0xBFFC1FFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 21 bits (1s in the mask) identify the network. The remaining 11 bits identify hosts within the network.
Split into Equal Subnets
Split 191.252.24.0/21 into 2 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 191.252.24.0/22 | 191.252.24.0 | 191.252.24.1 | 191.252.27.254 | 191.252.27.255 | 1,022 |
| 2 | 191.252.28.0/22 | 191.252.28.0 | 191.252.28.1 | 191.252.31.254 | 191.252.31.255 | 1,022 |
Split 191.252.24.0/21 into 4 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 191.252.24.0/23 | 191.252.24.0 | 191.252.24.1 | 191.252.25.254 | 191.252.25.255 | 510 |
| 2 | 191.252.26.0/23 | 191.252.26.0 | 191.252.26.1 | 191.252.27.254 | 191.252.27.255 | 510 |
| 3 | 191.252.28.0/23 | 191.252.28.0 | 191.252.28.1 | 191.252.29.254 | 191.252.29.255 | 510 |
| 4 | 191.252.30.0/23 | 191.252.30.0 | 191.252.30.1 | 191.252.31.254 | 191.252.31.255 | 510 |
Split 191.252.24.0/21 into 8 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 191.252.24.0/24 | 191.252.24.0 | 191.252.24.1 | 191.252.24.254 | 191.252.24.255 | 254 |
| 2 | 191.252.25.0/24 | 191.252.25.0 | 191.252.25.1 | 191.252.25.254 | 191.252.25.255 | 254 |
| 3 | 191.252.26.0/24 | 191.252.26.0 | 191.252.26.1 | 191.252.26.254 | 191.252.26.255 | 254 |
| 4 | 191.252.27.0/24 | 191.252.27.0 | 191.252.27.1 | 191.252.27.254 | 191.252.27.255 | 254 |
| 5 | 191.252.28.0/24 | 191.252.28.0 | 191.252.28.1 | 191.252.28.254 | 191.252.28.255 | 254 |
| 6 | 191.252.29.0/24 | 191.252.29.0 | 191.252.29.1 | 191.252.29.254 | 191.252.29.255 | 254 |
| 7 | 191.252.30.0/24 | 191.252.30.0 | 191.252.30.1 | 191.252.30.254 | 191.252.30.255 | 254 |
| 8 | 191.252.31.0/24 | 191.252.31.0 | 191.252.31.1 | 191.252.31.254 | 191.252.31.255 | 254 |
Split 191.252.24.0/21 into 16 equal /25 subnets (126 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 191.252.24.0/25 | 191.252.24.0 | 191.252.24.1 | 191.252.24.126 | 191.252.24.127 | 126 |
| 2 | 191.252.24.128/25 | 191.252.24.128 | 191.252.24.129 | 191.252.24.254 | 191.252.24.255 | 126 |
| 3 | 191.252.25.0/25 | 191.252.25.0 | 191.252.25.1 | 191.252.25.126 | 191.252.25.127 | 126 |
| 4 | 191.252.25.128/25 | 191.252.25.128 | 191.252.25.129 | 191.252.25.254 | 191.252.25.255 | 126 |
| 5 | 191.252.26.0/25 | 191.252.26.0 | 191.252.26.1 | 191.252.26.126 | 191.252.26.127 | 126 |
| 6 | 191.252.26.128/25 | 191.252.26.128 | 191.252.26.129 | 191.252.26.254 | 191.252.26.255 | 126 |
| 7 | 191.252.27.0/25 | 191.252.27.0 | 191.252.27.1 | 191.252.27.126 | 191.252.27.127 | 126 |
| 8 | 191.252.27.128/25 | 191.252.27.128 | 191.252.27.129 | 191.252.27.254 | 191.252.27.255 | 126 |
| 9 | 191.252.28.0/25 | 191.252.28.0 | 191.252.28.1 | 191.252.28.126 | 191.252.28.127 | 126 |
| 10 | 191.252.28.128/25 | 191.252.28.128 | 191.252.28.129 | 191.252.28.254 | 191.252.28.255 | 126 |
| 11 | 191.252.29.0/25 | 191.252.29.0 | 191.252.29.1 | 191.252.29.126 | 191.252.29.127 | 126 |
| 12 | 191.252.29.128/25 | 191.252.29.128 | 191.252.29.129 | 191.252.29.254 | 191.252.29.255 | 126 |
| 13 | 191.252.30.0/25 | 191.252.30.0 | 191.252.30.1 | 191.252.30.126 | 191.252.30.127 | 126 |
| 14 | 191.252.30.128/25 | 191.252.30.128 | 191.252.30.129 | 191.252.30.254 | 191.252.30.255 | 126 |
| 15 | 191.252.31.0/25 | 191.252.31.0 | 191.252.31.1 | 191.252.31.126 | 191.252.31.127 | 126 |
| 16 | 191.252.31.128/25 | 191.252.31.128 | 191.252.31.129 | 191.252.31.254 | 191.252.31.255 | 126 |