159.142.40.0/21
PublicClass B — /21 prefix — 2,046 usable hosts
Network address — the base address of the block (159.142.40.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 159.142.47.255 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 | 159.142.40.0/21 |
| Network Address | 159.142.40.0 |
| Broadcast Address | 159.142.47.255 |
| 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 | 159.142.40.1 |
| Last Usable IP | 159.142.47.254 |
| Network (Hex) | 0x9F8E2800 |
| Broadcast (Hex) | 0x9F8E2FFF |
| 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 159.142.40.0/21 into 2 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 159.142.40.0/22 | 159.142.40.0 | 159.142.40.1 | 159.142.43.254 | 159.142.43.255 | 1,022 |
| 2 | 159.142.44.0/22 | 159.142.44.0 | 159.142.44.1 | 159.142.47.254 | 159.142.47.255 | 1,022 |
Split 159.142.40.0/21 into 4 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 159.142.40.0/23 | 159.142.40.0 | 159.142.40.1 | 159.142.41.254 | 159.142.41.255 | 510 |
| 2 | 159.142.42.0/23 | 159.142.42.0 | 159.142.42.1 | 159.142.43.254 | 159.142.43.255 | 510 |
| 3 | 159.142.44.0/23 | 159.142.44.0 | 159.142.44.1 | 159.142.45.254 | 159.142.45.255 | 510 |
| 4 | 159.142.46.0/23 | 159.142.46.0 | 159.142.46.1 | 159.142.47.254 | 159.142.47.255 | 510 |
Split 159.142.40.0/21 into 8 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 159.142.40.0/24 | 159.142.40.0 | 159.142.40.1 | 159.142.40.254 | 159.142.40.255 | 254 |
| 2 | 159.142.41.0/24 | 159.142.41.0 | 159.142.41.1 | 159.142.41.254 | 159.142.41.255 | 254 |
| 3 | 159.142.42.0/24 | 159.142.42.0 | 159.142.42.1 | 159.142.42.254 | 159.142.42.255 | 254 |
| 4 | 159.142.43.0/24 | 159.142.43.0 | 159.142.43.1 | 159.142.43.254 | 159.142.43.255 | 254 |
| 5 | 159.142.44.0/24 | 159.142.44.0 | 159.142.44.1 | 159.142.44.254 | 159.142.44.255 | 254 |
| 6 | 159.142.45.0/24 | 159.142.45.0 | 159.142.45.1 | 159.142.45.254 | 159.142.45.255 | 254 |
| 7 | 159.142.46.0/24 | 159.142.46.0 | 159.142.46.1 | 159.142.46.254 | 159.142.46.255 | 254 |
| 8 | 159.142.47.0/24 | 159.142.47.0 | 159.142.47.1 | 159.142.47.254 | 159.142.47.255 | 254 |
Split 159.142.40.0/21 into 16 equal /25 subnets (126 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 159.142.40.0/25 | 159.142.40.0 | 159.142.40.1 | 159.142.40.126 | 159.142.40.127 | 126 |
| 2 | 159.142.40.128/25 | 159.142.40.128 | 159.142.40.129 | 159.142.40.254 | 159.142.40.255 | 126 |
| 3 | 159.142.41.0/25 | 159.142.41.0 | 159.142.41.1 | 159.142.41.126 | 159.142.41.127 | 126 |
| 4 | 159.142.41.128/25 | 159.142.41.128 | 159.142.41.129 | 159.142.41.254 | 159.142.41.255 | 126 |
| 5 | 159.142.42.0/25 | 159.142.42.0 | 159.142.42.1 | 159.142.42.126 | 159.142.42.127 | 126 |
| 6 | 159.142.42.128/25 | 159.142.42.128 | 159.142.42.129 | 159.142.42.254 | 159.142.42.255 | 126 |
| 7 | 159.142.43.0/25 | 159.142.43.0 | 159.142.43.1 | 159.142.43.126 | 159.142.43.127 | 126 |
| 8 | 159.142.43.128/25 | 159.142.43.128 | 159.142.43.129 | 159.142.43.254 | 159.142.43.255 | 126 |
| 9 | 159.142.44.0/25 | 159.142.44.0 | 159.142.44.1 | 159.142.44.126 | 159.142.44.127 | 126 |
| 10 | 159.142.44.128/25 | 159.142.44.128 | 159.142.44.129 | 159.142.44.254 | 159.142.44.255 | 126 |
| 11 | 159.142.45.0/25 | 159.142.45.0 | 159.142.45.1 | 159.142.45.126 | 159.142.45.127 | 126 |
| 12 | 159.142.45.128/25 | 159.142.45.128 | 159.142.45.129 | 159.142.45.254 | 159.142.45.255 | 126 |
| 13 | 159.142.46.0/25 | 159.142.46.0 | 159.142.46.1 | 159.142.46.126 | 159.142.46.127 | 126 |
| 14 | 159.142.46.128/25 | 159.142.46.128 | 159.142.46.129 | 159.142.46.254 | 159.142.46.255 | 126 |
| 15 | 159.142.47.0/25 | 159.142.47.0 | 159.142.47.1 | 159.142.47.126 | 159.142.47.127 | 126 |
| 16 | 159.142.47.128/25 | 159.142.47.128 | 159.142.47.129 | 159.142.47.254 | 159.142.47.255 | 126 |