reCAPTCHA example form page

<!DOCTYPE html>
<html>
<head>
    <script src="https://www.google.com/recaptcha/api.js"></script>
</head>
<body>
<form method="POST">
    <div class="g-recaptcha" data-sitekey="YOUR_PUBLIC_KEY">
</div>
</form>
</body>
</html>