126.252.248.0/21
PublicClass A — /21 prefix — 2,046 usable hosts
Network address — the base address of the block (126.252.248.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 126.252.255.255 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 | 126.252.248.0/21 |
| Network Address | 126.252.248.0 |
| Broadcast Address | 126.252.255.255 |
| Subnet Mask | 255.255.248.0 |
| Wildcard Mask | 0.0.7.255 |
| Prefix Length | /21 |
| IP Address Class | Class A |
| Total IP Addresses | 2,048 |
| Usable Host Addresses | 2,046 |
| First Usable IP | 126.252.248.1 |
| Last Usable IP | 126.252.255.254 |
| Network (Hex) | 0x7EFCF800 |
| Broadcast (Hex) | 0x7EFCFFFF |
| 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 126.252.248.0/21 into 2 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 126.252.248.0/22 | 126.252.248.0 | 126.252.248.1 | 126.252.251.254 | 126.252.251.255 | 1,022 |
| 2 | 126.252.252.0/22 | 126.252.252.0 | 126.252.252.1 | 126.252.255.254 | 126.252.255.255 | 1,022 |
Split 126.252.248.0/21 into 4 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 126.252.248.0/23 | 126.252.248.0 | 126.252.248.1 | 126.252.249.254 | 126.252.249.255 | 510 |
| 2 | 126.252.250.0/23 | 126.252.250.0 | 126.252.250.1 | 126.252.251.254 | 126.252.251.255 | 510 |
| 3 | 126.252.252.0/23 | 126.252.252.0 | 126.252.252.1 | 126.252.253.254 | 126.252.253.255 | 510 |
| 4 | 126.252.254.0/23 | 126.252.254.0 | 126.252.254.1 | 126.252.255.254 | 126.252.255.255 | 510 |
Split 126.252.248.0/21 into 8 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 126.252.248.0/24 | 126.252.248.0 | 126.252.248.1 | 126.252.248.254 | 126.252.248.255 | 254 |
| 2 | 126.252.249.0/24 | 126.252.249.0 | 126.252.249.1 | 126.252.249.254 | 126.252.249.255 | 254 |
| 3 | 126.252.250.0/24 | 126.252.250.0 | 126.252.250.1 | 126.252.250.254 | 126.252.250.255 | 254 |
| 4 | 126.252.251.0/24 | 126.252.251.0 | 126.252.251.1 | 126.252.251.254 | 126.252.251.255 | 254 |
| 5 | 126.252.252.0/24 | 126.252.252.0 | 126.252.252.1 | 126.252.252.254 | 126.252.252.255 | 254 |
| 6 | 126.252.253.0/24 | 126.252.253.0 | 126.252.253.1 | 126.252.253.254 | 126.252.253.255 | 254 |
| 7 | 126.252.254.0/24 | 126.252.254.0 | 126.252.254.1 | 126.252.254.254 | 126.252.254.255 | 254 |
| 8 | 126.252.255.0/24 | 126.252.255.0 | 126.252.255.1 | 126.252.255.254 | 126.252.255.255 | 254 |
Split 126.252.248.0/21 into 16 equal /25 subnets (126 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 126.252.248.0/25 | 126.252.248.0 | 126.252.248.1 | 126.252.248.126 | 126.252.248.127 | 126 |
| 2 | 126.252.248.128/25 | 126.252.248.128 | 126.252.248.129 | 126.252.248.254 | 126.252.248.255 | 126 |
| 3 | 126.252.249.0/25 | 126.252.249.0 | 126.252.249.1 | 126.252.249.126 | 126.252.249.127 | 126 |
| 4 | 126.252.249.128/25 | 126.252.249.128 | 126.252.249.129 | 126.252.249.254 | 126.252.249.255 | 126 |
| 5 | 126.252.250.0/25 | 126.252.250.0 | 126.252.250.1 | 126.252.250.126 | 126.252.250.127 | 126 |
| 6 | 126.252.250.128/25 | 126.252.250.128 | 126.252.250.129 | 126.252.250.254 | 126.252.250.255 | 126 |
| 7 | 126.252.251.0/25 | 126.252.251.0 | 126.252.251.1 | 126.252.251.126 | 126.252.251.127 | 126 |
| 8 | 126.252.251.128/25 | 126.252.251.128 | 126.252.251.129 | 126.252.251.254 | 126.252.251.255 | 126 |
| 9 | 126.252.252.0/25 | 126.252.252.0 | 126.252.252.1 | 126.252.252.126 | 126.252.252.127 | 126 |
| 10 | 126.252.252.128/25 | 126.252.252.128 | 126.252.252.129 | 126.252.252.254 | 126.252.252.255 | 126 |
| 11 | 126.252.253.0/25 | 126.252.253.0 | 126.252.253.1 | 126.252.253.126 | 126.252.253.127 | 126 |
| 12 | 126.252.253.128/25 | 126.252.253.128 | 126.252.253.129 | 126.252.253.254 | 126.252.253.255 | 126 |
| 13 | 126.252.254.0/25 | 126.252.254.0 | 126.252.254.1 | 126.252.254.126 | 126.252.254.127 | 126 |
| 14 | 126.252.254.128/25 | 126.252.254.128 | 126.252.254.129 | 126.252.254.254 | 126.252.254.255 | 126 |
| 15 | 126.252.255.0/25 | 126.252.255.0 | 126.252.255.1 | 126.252.255.126 | 126.252.255.127 | 126 |
| 16 | 126.252.255.128/25 | 126.252.255.128 | 126.252.255.129 | 126.252.255.254 | 126.252.255.255 | 126 |