SIDs and account names - a handy function for this

A handy function to get account names from SIDs and SIDs from account name, receiving local SIDs from remote machine will follow.

function Get-SID_NAME(
    [Parameter(Position=2)][string]$domain=$env:userdomain,
    [Parameter(Mandatory=$True,Position=1)][string]$search,
    [switch]$Local)
{
 if($search -match '\\'){
    $domain=$search.Split('\')[0]
    $search=$search.Split('\')[1]
    }
 if($search -match '^S-1-5-21-'){
    $objSID = New-Object System.Security.Principal.SecurityIdentifier($search)
    $objUser = $objSID.Translate( [System.Security.Principal.NTAccount])
    return $objUser.Value
    }else{
        if($Local){
            $objUser = New-Object System.Security.Principal.NTAccount($search)
            $strSID = $objUser.Translate([System.Security.Principal.SecurityIdentifier])
            return $strSID.Value
        } else {
            $objUser = New-Object System.Security.Principal.NTAccount($domain, $search)
            $strSID = $objUser.Translate([System.Security.Principal.SecurityIdentifier])
            return $strSID.Value
        }
    }
}


Source from most of the code :

https://technet.microsoft.com/en-us/library/ff730940.aspx