Test passwords against https://haveibeenpwned.com/Passwords

testpassword.ps1

function Test-Password {
    [CmdletBinding()]
    param (
        [Parameter(ValueFromPipeline=$true)]
        [string]$Password
    )
    
    begin {
        [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
    }
    
    process {
        $passwordBytes = [System.Text.Encoding]::UTF8.GetBytes($Password)
        $sha1 = New-Object System.Security.Cryptography.SHA1Managed
        $hash = $sha1.ComputeHash($passwordBytes)
        $hexHash = [System.BitConverter]::ToString($hash).Replace("-", "")

        $first5 = $hexHash.Substring(0,5)
        $rest = $hexHash.Substring(5)

        $content = (Invoke-WebRequest https://api.pwnedpasswords.com/range/$first5).Content
        $content.Split() | where {$_ -like "$rest*"}
    }
}