Converting a SID to a Username in PowerShell

In the world of Windows operating systems, each user or group account is assigned a unique identifier known as a Security Identifier (SID). This SID is used internally by Windows to manage and track user accounts, permissions, and resources. However, interpreting a SID directly can be difficult since it is not human-readable.

If you’ve ever come across a SID and need to translate it to a more understandable username or group name, PowerShell provides a simple and effective way to perform this conversion.

In this blog, we’ll explore how to convert a SID to a username using PowerShell.

What is a SID?

A Security Identifier (SID) is a unique value used to identify a user or group account within Windows. SIDs are created when the account is first created, and they never change, even if the account’s username is modified. Windows uses these SIDs to manage access control and security settings across the system.

Converting a SID to a Username Using PowerShell

PowerShell provides a straightforward way to translate a SID into a readable username or group name using the System.Security.Principal.WindowsIdentity class.

# Define the SID you want to convert
$sid = "S-1-5-21-3130759052-3945292234-2235697063-1104"  # Replace this with the actual SID

# Create a SecurityIdentifier object
$user = New-Object System.Security.Principal.SecurityIdentifier($sid)

# Translate the SID to a username
$username = $user.Translate([System.Security.Principal.NTAccount]).Value

# Output the result
$username

Step 1: We start by assigning the SID you want to convert to a variable ($sid).

Step 2: Using the System.Security.Principal.SecurityIdentifier class, we create a new object that represents the SID.

Step 3: The Translate() method translates the SID into a human-readable form, in this case, a username or group name.

Step 4: The result is stored in the $username variable, and you can output this to see the corresponding username or group.