151.8.208.0/20
PublicClass B — /20 prefix — 4,094 usable hosts
Network address — the base address of the block (151.8.208.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 151.8.223.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 4,094 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.240.0 is the dotted-decimal equivalent of /20. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 151.8.208.0/20 |
| Network Address | 151.8.208.0 |
| Broadcast Address | 151.8.223.255 |
| Subnet Mask | 255.255.240.0 |
| Wildcard Mask | 0.0.15.255 |
| Prefix Length | /20 |
| IP Address Class | Class B |
| Total IP Addresses | 4,096 |
| Usable Host Addresses | 4,094 |
| First Usable IP | 151.8.208.1 |
| Last Usable IP | 151.8.223.254 |
| Network (Hex) | 0x9708D000 |
| Broadcast (Hex) | 0x9708DFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 20 bits (1s in the mask) identify the network. The remaining 12 bits identify hosts within the network.
Split into Equal Subnets
Split 151.8.208.0/20 into 2 equal /21 subnets (2,046 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 151.8.208.0/21 | 151.8.208.0 | 151.8.208.1 | 151.8.215.254 | 151.8.215.255 | 2,046 |
| 2 | 151.8.216.0/21 | 151.8.216.0 | 151.8.216.1 | 151.8.223.254 | 151.8.223.255 | 2,046 |
Split 151.8.208.0/20 into 4 equal /22 subnets (1,022 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 151.8.208.0/22 | 151.8.208.0 | 151.8.208.1 | 151.8.211.254 | 151.8.211.255 | 1,022 |
| 2 | 151.8.212.0/22 | 151.8.212.0 | 151.8.212.1 | 151.8.215.254 | 151.8.215.255 | 1,022 |
| 3 | 151.8.216.0/22 | 151.8.216.0 | 151.8.216.1 | 151.8.219.254 | 151.8.219.255 | 1,022 |
| 4 | 151.8.220.0/22 | 151.8.220.0 | 151.8.220.1 | 151.8.223.254 | 151.8.223.255 | 1,022 |
Split 151.8.208.0/20 into 8 equal /23 subnets (510 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 151.8.208.0/23 | 151.8.208.0 | 151.8.208.1 | 151.8.209.254 | 151.8.209.255 | 510 |
| 2 | 151.8.210.0/23 | 151.8.210.0 | 151.8.210.1 | 151.8.211.254 | 151.8.211.255 | 510 |
| 3 | 151.8.212.0/23 | 151.8.212.0 | 151.8.212.1 | 151.8.213.254 | 151.8.213.255 | 510 |
| 4 | 151.8.214.0/23 | 151.8.214.0 | 151.8.214.1 | 151.8.215.254 | 151.8.215.255 | 510 |
| 5 | 151.8.216.0/23 | 151.8.216.0 | 151.8.216.1 | 151.8.217.254 | 151.8.217.255 | 510 |
| 6 | 151.8.218.0/23 | 151.8.218.0 | 151.8.218.1 | 151.8.219.254 | 151.8.219.255 | 510 |
| 7 | 151.8.220.0/23 | 151.8.220.0 | 151.8.220.1 | 151.8.221.254 | 151.8.221.255 | 510 |
| 8 | 151.8.222.0/23 | 151.8.222.0 | 151.8.222.1 | 151.8.223.254 | 151.8.223.255 | 510 |
Split 151.8.208.0/20 into 16 equal /24 subnets (254 usable hosts each).
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 151.8.208.0/24 | 151.8.208.0 | 151.8.208.1 | 151.8.208.254 | 151.8.208.255 | 254 |
| 2 | 151.8.209.0/24 | 151.8.209.0 | 151.8.209.1 | 151.8.209.254 | 151.8.209.255 | 254 |
| 3 | 151.8.210.0/24 | 151.8.210.0 | 151.8.210.1 | 151.8.210.254 | 151.8.210.255 | 254 |
| 4 | 151.8.211.0/24 | 151.8.211.0 | 151.8.211.1 | 151.8.211.254 | 151.8.211.255 | 254 |
| 5 | 151.8.212.0/24 | 151.8.212.0 | 151.8.212.1 | 151.8.212.254 | 151.8.212.255 | 254 |
| 6 | 151.8.213.0/24 | 151.8.213.0 | 151.8.213.1 | 151.8.213.254 | 151.8.213.255 | 254 |
| 7 | 151.8.214.0/24 | 151.8.214.0 | 151.8.214.1 | 151.8.214.254 | 151.8.214.255 | 254 |
| 8 | 151.8.215.0/24 | 151.8.215.0 | 151.8.215.1 | 151.8.215.254 | 151.8.215.255 | 254 |
| 9 | 151.8.216.0/24 | 151.8.216.0 | 151.8.216.1 | 151.8.216.254 | 151.8.216.255 | 254 |
| 10 | 151.8.217.0/24 | 151.8.217.0 | 151.8.217.1 | 151.8.217.254 | 151.8.217.255 | 254 |
| 11 | 151.8.218.0/24 | 151.8.218.0 | 151.8.218.1 | 151.8.218.254 | 151.8.218.255 | 254 |
| 12 | 151.8.219.0/24 | 151.8.219.0 | 151.8.219.1 | 151.8.219.254 | 151.8.219.255 | 254 |
| 13 | 151.8.220.0/24 | 151.8.220.0 | 151.8.220.1 | 151.8.220.254 | 151.8.220.255 | 254 |
| 14 | 151.8.221.0/24 | 151.8.221.0 | 151.8.221.1 | 151.8.221.254 | 151.8.221.255 | 254 |
| 15 | 151.8.222.0/24 | 151.8.222.0 | 151.8.222.1 | 151.8.222.254 | 151.8.222.255 | 254 |
| 16 | 151.8.223.0/24 | 151.8.223.0 | 151.8.223.1 | 151.8.223.254 | 151.8.223.255 | 254 |