Q&A: What was my PowerShell version, again?

Okay, so you're sitting next to a customer's server, and need to run some PowerShell commands. You check the command specs from the Internet, and notice that a particular command is only available in PowerShell 4.0. Can you run this command or not?

Although you can somewhat predict the PowerShell version from the OS version, this isn't a fool-proof method. Similarly, if you need to check the version number in a script, you need to have a suitable command for it.

There's no "Get-PSVersion" command in PowerShell, but there's one cmdlet that comes close, and two neat variables that you can use.

First, there's the command Get-Host. This command returns information about the PowerShell host, and the returned object contains a property called Version. This is the PowerShell version you are after. For example:

PS C:\Users\jani.jarvinen> get-host

Name             : ConsoleHost
Version          : 4.0
InstanceId       : 743335e5-ea8e-498e-9826-c9a40b8a7640
UI               : System.Management.Automation.Internal.Host.InternalHostUserInterface
CurrentCulture   : fi-FI
CurrentUICulture : en-US
PrivateData      : Microsoft.PowerShell.ConsoleHost+ConsoleColorProxy
IsRunspacePushed : False
Runspace         : System.Management.Automation.Runspaces.LocalRunspace

In addition to the Get-Host cmdlet, you can also directly refer to a global variable called $host. This variable contains the same value as Get-Host would return.

With either Get-Host or $host, you can read the PowerShell's major version number from the property Version.Major.

Finally, there's a somewhat less-known variable called $PSVersionTable. If you query the value of this variable, the results look like this:

PS C:\Users\jani.jarvinen> $psversiontable

Name                           Value
----                           -----
PSVersion                      4.0
WSManStackVersion              3.0
SerializationVersion           1.1.0.1
CLRVersion                     4.0.30319.34014
BuildVersion                   6.3.9600.17090
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0}
PSRemotingProtocolVersion      2.2

These results are from a Windows 8.1 machine with the latest updates. Notice how the property called PSVersion gives you the results you need.

Notice also the other useful properties: CLRVersion and PSCompatibleVersionings.