remove domain from url dynamically

function remove_domain($url) {
    $domain = str_replace('https://', '', $url);
    $domain = str_replace('http://', '', $domain);
    $domain = str_replace('www.', '', $domain);
    $domain = strstr($domain, '/', true);
    return $domain;
}
remove_domain('https://www.google.com/');