PowerShell-Subnet

A cross-platform PowerShell module for cmdlets related to network subnet calculations.

Installation

The module is published in the PSGallery, so if you have PowerShell 5 or newer can be installed by running:

Install-Module Subnet -Scope CurrentUser

Or:

Install-PSResource Subnet

Usage

Get the subnet details for a specified network address and mask using slash notation:

Get-Subnet 192.168.4.56/24

Result:

IPAddress        : 192.168.4.56
MaskBits         : 24
NetworkAddress   : 192.168.4.0
BroadcastAddress : 192.168.4.255
SubnetMask       : 255.255.255.0
NetworkClass     : C
Range            : 192.168.4.0 ~ 192.168.4.255
HostAddresses    : {192.168.4.1, 192.168.4.2, 192.168.4.3, 192.168.4.4...}
HostAddressCount : 254

Get the subnet details for a specified network address and mask, as specified via the -MaskBits parameter:

Get-Subnet -IP 192.168.4.56 -MaskBits 20

Result:

IPAddress        : 192.168.4.56
MaskBits         : 20
NetworkAddress   : 192.168.0.0
BroadcastAddress : 192.168.15.255
SubnetMask       : 255.255.240.0
NetworkClass     : C
Range            : 192.168.0.0 ~ 192.168.15.255
HostAddresses    : {192.168.0.1, 192.168.0.2, 192.168.0.3, 192.168.0.4...}
HostAddressCount : 4094

Get the subnet details for the current local network IP (works on Windows, Linux and macOS):

Get-Subnet

Get just the list of host addresses for a subnet, without the rest of the subnet detail object. Get-SubnetHostAddress returns [ipaddress] objects by default; use -AsString for plain strings instead:

Get-SubnetHostAddress 192.168.4.56/29 -AsString

Result:

192.168.4.57
192.168.4.58
192.168.4.59
192.168.4.60
192.168.4.61
192.168.4.62

Get-SubnetHostAddress also accepts the object output by Get-Subnet via the pipeline:

Get-Subnet 192.168.4.56/29 | Get-SubnetHostAddress

Test whether an IP address is within the private (RFC 1918) address space:

Test-PrivateIP -IP 172.16.1.2

Result:

True

Or whether it's within the public address space:

Test-PublicIP -IP 8.8.8.8

Result:

True

Other Features

• Get-Subnet's HostAddressCount is always calculated, regardless of subnet size, since it's just arithmetic. If the subnet size specified is larger than a /16, Get-Subnet will not return the full list of individual HostAddresses by default, and instead warn that this would take some time. If you want to force the return of host addresses for these subnets, use -Force.
• Get-SubnetHostAddress, since returning host addresses is its only job, always calculates and returns them regardless of subnet size -- there's no -Force needed. It still warns if the subnet is larger than /16, since that may take some time.
• If no subnet mask size is specified, the cmdlets will use the default size for the class of address, and show a warning that they have done so.