172.31.1.128/27
Private (RFC 1918) RFC 1918Class B — /27 prefix — 30 usable hosts
Network address — the base address of the block (172.31.1.128). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 172.31.1.159 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 30 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 255.255.255.224 is the dotted-decimal equivalent of /27. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 172.31.1.128/27 |
| Network Address | 172.31.1.128 |
| Broadcast Address | 172.31.1.159 |
| Subnet Mask | 255.255.255.224 |
| Wildcard Mask | 0.0.0.31 |
| Prefix Length | /27 |
| IP Address Class | Class B |
| Total IP Addresses | 32 |
| Usable Host Addresses | 30 |
| First Usable IP | 172.31.1.129 |
| Last Usable IP | 172.31.1.158 |
| Network (Hex) | 0xAC1F0180 |
| Broadcast (Hex) | 0xAC1F019F |
| Governing RFC | RFC 1918 |
| Address Type | Private (RFC 1918) |
Binary Representation
The first 27 bits (1s in the mask) identify the network. The remaining 5 bits identify hosts within the network.
Subnet Breakdown — splitting into /28
This /27 block can be divided into 2 /28 subnets.
| CIDR | Network | Broadcast | First Usable | Last Usable | Hosts |
|---|---|---|---|---|---|
| 172.31.1.128/28 | 172.31.1.128 | 172.31.1.143 | 172.31.1.129 | 172.31.1.142 | 14 |
| 172.31.1.144/28 | 172.31.1.144 | 172.31.1.159 | 172.31.1.145 | 172.31.1.158 | 14 |
IP Address Sample
Showing first 16 of 32 total IPs.