40.88.248.0/21
PublicClass A — /21 prefix — 2,046 usable hosts
Network address — the base address of the block (40.88.248.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 40.88.255.255 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 | 40.88.248.0/21 |
| Network Address | 40.88.248.0 |
| Broadcast Address | 40.88.255.255 |
| 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 | 40.88.248.1 |
| Last Usable IP | 40.88.255.254 |
| Network (Hex) | 0x2858F800 |
| Broadcast (Hex) | 0x2858FFFF |
| 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 40.88.248.0/21 into 2 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 40.88.248.0/22 | 40.88.248.0 | 40.88.248.1 | 40.88.251.254 | 40.88.251.255 | 1,022 |
| 2 | 40.88.252.0/22 | 40.88.252.0 | 40.88.252.1 | 40.88.255.254 | 40.88.255.255 | 1,022 |
Split 40.88.248.0/21 into 4 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 40.88.248.0/23 | 40.88.248.0 | 40.88.248.1 | 40.88.249.254 | 40.88.249.255 | 510 |
| 2 | 40.88.250.0/23 | 40.88.250.0 | 40.88.250.1 | 40.88.251.254 | 40.88.251.255 | 510 |
| 3 | 40.88.252.0/23 | 40.88.252.0 | 40.88.252.1 | 40.88.253.254 | 40.88.253.255 | 510 |
| 4 | 40.88.254.0/23 | 40.88.254.0 | 40.88.254.1 | 40.88.255.254 | 40.88.255.255 | 510 |
Split 40.88.248.0/21 into 8 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 40.88.248.0/24 | 40.88.248.0 | 40.88.248.1 | 40.88.248.254 | 40.88.248.255 | 254 |
| 2 | 40.88.249.0/24 | 40.88.249.0 | 40.88.249.1 | 40.88.249.254 | 40.88.249.255 | 254 |
| 3 | 40.88.250.0/24 | 40.88.250.0 | 40.88.250.1 | 40.88.250.254 | 40.88.250.255 | 254 |
| 4 | 40.88.251.0/24 | 40.88.251.0 | 40.88.251.1 | 40.88.251.254 | 40.88.251.255 | 254 |
| 5 | 40.88.252.0/24 | 40.88.252.0 | 40.88.252.1 | 40.88.252.254 | 40.88.252.255 | 254 |
| 6 | 40.88.253.0/24 | 40.88.253.0 | 40.88.253.1 | 40.88.253.254 | 40.88.253.255 | 254 |
| 7 | 40.88.254.0/24 | 40.88.254.0 | 40.88.254.1 | 40.88.254.254 | 40.88.254.255 | 254 |
| 8 | 40.88.255.0/24 | 40.88.255.0 | 40.88.255.1 | 40.88.255.254 | 40.88.255.255 | 254 |
Split 40.88.248.0/21 into 16 equal /25 subnets (126 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 40.88.248.0/25 | 40.88.248.0 | 40.88.248.1 | 40.88.248.126 | 40.88.248.127 | 126 |
| 2 | 40.88.248.128/25 | 40.88.248.128 | 40.88.248.129 | 40.88.248.254 | 40.88.248.255 | 126 |
| 3 | 40.88.249.0/25 | 40.88.249.0 | 40.88.249.1 | 40.88.249.126 | 40.88.249.127 | 126 |
| 4 | 40.88.249.128/25 | 40.88.249.128 | 40.88.249.129 | 40.88.249.254 | 40.88.249.255 | 126 |
| 5 | 40.88.250.0/25 | 40.88.250.0 | 40.88.250.1 | 40.88.250.126 | 40.88.250.127 | 126 |
| 6 | 40.88.250.128/25 | 40.88.250.128 | 40.88.250.129 | 40.88.250.254 | 40.88.250.255 | 126 |
| 7 | 40.88.251.0/25 | 40.88.251.0 | 40.88.251.1 | 40.88.251.126 | 40.88.251.127 | 126 |
| 8 | 40.88.251.128/25 | 40.88.251.128 | 40.88.251.129 | 40.88.251.254 | 40.88.251.255 | 126 |
| 9 | 40.88.252.0/25 | 40.88.252.0 | 40.88.252.1 | 40.88.252.126 | 40.88.252.127 | 126 |
| 10 | 40.88.252.128/25 | 40.88.252.128 | 40.88.252.129 | 40.88.252.254 | 40.88.252.255 | 126 |
| 11 | 40.88.253.0/25 | 40.88.253.0 | 40.88.253.1 | 40.88.253.126 | 40.88.253.127 | 126 |
| 12 | 40.88.253.128/25 | 40.88.253.128 | 40.88.253.129 | 40.88.253.254 | 40.88.253.255 | 126 |
| 13 | 40.88.254.0/25 | 40.88.254.0 | 40.88.254.1 | 40.88.254.126 | 40.88.254.127 | 126 |
| 14 | 40.88.254.128/25 | 40.88.254.128 | 40.88.254.129 | 40.88.254.254 | 40.88.254.255 | 126 |
| 15 | 40.88.255.0/25 | 40.88.255.0 | 40.88.255.1 | 40.88.255.126 | 40.88.255.127 | 126 |
| 16 | 40.88.255.128/25 | 40.88.255.128 | 40.88.255.129 | 40.88.255.254 | 40.88.255.255 | 126 |