255.210.160.0/21
PublicClass E (Reserved) — /21 prefix — 2,046 usable hosts
Network address — the base address of the block (255.210.160.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 255.210.167.255 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 | 255.210.160.0/21 |
| Network Address | 255.210.160.0 |
| Broadcast Address | 255.210.167.255 |
| Subnet Mask | 255.255.248.0 |
| Wildcard Mask | 0.0.7.255 |
| Prefix Length | /21 |
| IP Address Class | Class E (Reserved) |
| Total IP Addresses | 2,048 |
| Usable Host Addresses | 2,046 |
| First Usable IP | 255.210.160.1 |
| Last Usable IP | 255.210.167.254 |
| Network (Hex) | 0xFFD2A000 |
| Broadcast (Hex) | 0xFFD2A7FF |
| 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 255.210.160.0/21 into 2 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 255.210.160.0/22 | 255.210.160.0 | 255.210.160.1 | 255.210.163.254 | 255.210.163.255 | 1,022 |
| 2 | 255.210.164.0/22 | 255.210.164.0 | 255.210.164.1 | 255.210.167.254 | 255.210.167.255 | 1,022 |
Split 255.210.160.0/21 into 4 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 255.210.160.0/23 | 255.210.160.0 | 255.210.160.1 | 255.210.161.254 | 255.210.161.255 | 510 |
| 2 | 255.210.162.0/23 | 255.210.162.0 | 255.210.162.1 | 255.210.163.254 | 255.210.163.255 | 510 |
| 3 | 255.210.164.0/23 | 255.210.164.0 | 255.210.164.1 | 255.210.165.254 | 255.210.165.255 | 510 |
| 4 | 255.210.166.0/23 | 255.210.166.0 | 255.210.166.1 | 255.210.167.254 | 255.210.167.255 | 510 |
Split 255.210.160.0/21 into 8 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 255.210.160.0/24 | 255.210.160.0 | 255.210.160.1 | 255.210.160.254 | 255.210.160.255 | 254 |
| 2 | 255.210.161.0/24 | 255.210.161.0 | 255.210.161.1 | 255.210.161.254 | 255.210.161.255 | 254 |
| 3 | 255.210.162.0/24 | 255.210.162.0 | 255.210.162.1 | 255.210.162.254 | 255.210.162.255 | 254 |
| 4 | 255.210.163.0/24 | 255.210.163.0 | 255.210.163.1 | 255.210.163.254 | 255.210.163.255 | 254 |
| 5 | 255.210.164.0/24 | 255.210.164.0 | 255.210.164.1 | 255.210.164.254 | 255.210.164.255 | 254 |
| 6 | 255.210.165.0/24 | 255.210.165.0 | 255.210.165.1 | 255.210.165.254 | 255.210.165.255 | 254 |
| 7 | 255.210.166.0/24 | 255.210.166.0 | 255.210.166.1 | 255.210.166.254 | 255.210.166.255 | 254 |
| 8 | 255.210.167.0/24 | 255.210.167.0 | 255.210.167.1 | 255.210.167.254 | 255.210.167.255 | 254 |
Split 255.210.160.0/21 into 16 equal /25 subnets (126 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 255.210.160.0/25 | 255.210.160.0 | 255.210.160.1 | 255.210.160.126 | 255.210.160.127 | 126 |
| 2 | 255.210.160.128/25 | 255.210.160.128 | 255.210.160.129 | 255.210.160.254 | 255.210.160.255 | 126 |
| 3 | 255.210.161.0/25 | 255.210.161.0 | 255.210.161.1 | 255.210.161.126 | 255.210.161.127 | 126 |
| 4 | 255.210.161.128/25 | 255.210.161.128 | 255.210.161.129 | 255.210.161.254 | 255.210.161.255 | 126 |
| 5 | 255.210.162.0/25 | 255.210.162.0 | 255.210.162.1 | 255.210.162.126 | 255.210.162.127 | 126 |
| 6 | 255.210.162.128/25 | 255.210.162.128 | 255.210.162.129 | 255.210.162.254 | 255.210.162.255 | 126 |
| 7 | 255.210.163.0/25 | 255.210.163.0 | 255.210.163.1 | 255.210.163.126 | 255.210.163.127 | 126 |
| 8 | 255.210.163.128/25 | 255.210.163.128 | 255.210.163.129 | 255.210.163.254 | 255.210.163.255 | 126 |
| 9 | 255.210.164.0/25 | 255.210.164.0 | 255.210.164.1 | 255.210.164.126 | 255.210.164.127 | 126 |
| 10 | 255.210.164.128/25 | 255.210.164.128 | 255.210.164.129 | 255.210.164.254 | 255.210.164.255 | 126 |
| 11 | 255.210.165.0/25 | 255.210.165.0 | 255.210.165.1 | 255.210.165.126 | 255.210.165.127 | 126 |
| 12 | 255.210.165.128/25 | 255.210.165.128 | 255.210.165.129 | 255.210.165.254 | 255.210.165.255 | 126 |
| 13 | 255.210.166.0/25 | 255.210.166.0 | 255.210.166.1 | 255.210.166.126 | 255.210.166.127 | 126 |
| 14 | 255.210.166.128/25 | 255.210.166.128 | 255.210.166.129 | 255.210.166.254 | 255.210.166.255 | 126 |
| 15 | 255.210.167.0/25 | 255.210.167.0 | 255.210.167.1 | 255.210.167.126 | 255.210.167.127 | 126 |
| 16 | 255.210.167.128/25 | 255.210.167.128 | 255.210.167.129 | 255.210.167.254 | 255.210.167.255 | 126 |