function validateRecaptcha() {
    $token = $_POST['token'];
    $action = $_POST['action'];
    $secret = 'your_secret';

    if(isset($token) && !empty($token)){
        $verifyURL = 'https://www.google.com/recaptcha/api/siteverify?secret=' . urlencode($secret) .  '&response=' . urlencode($token);
        //get verify response data
        $verifyResponse = file_get_contents($verifyURL);
        $responseData = json_decode($verifyResponse);

        if($responseData && $responseData->success && $responseData->action === $action) {
            return $responseData->score;
        }

        // maybe check error codes in responseData here and return them.
    } else {
        return "No Token";
    }
}