To protect your sites from automated spam, TailStatic supports [Google reCAPTCHA v3](https://developers.google.com/recaptcha/docs/v3). When enabled, visitors must pass a silent background check before their form submission is accepted.

### Configuration

You can enable captcha on a site-by-site basis in the site settings.

1. Go to your site dashboard.
2. Navigate to the **Site Configuration** and **Captcha** section.
3. Enter your reCAPTCHA **Site Key** and **Secret Key**.
4. Save the settings.

### Form Behavior

Once captcha is configured for a site, you can enable it on individual forms from form settings.

* **Automatic Validation:** In your HTML form, include [captcha liquid tag](/docs/captcha-setup) and TailStatic will automatically include the necessary JavaScript on your page and validate the captcha token when the form is submitted.
* **Invisible Protection:** reCAPTCHA v3 does not require visitors to click a box or solve a puzzle; it analyzes their behavior to determine if they are likely a human.

### Common Validation Failures

If a form submission fails due to captcha:
* **Invalid Keys:** Double-check that you have entered the correct Site Key and Secret Key in site configuration.
* **Low Score:** If reCAPTCHA determines that a visitor is likely a bot, the submission will be blocked. You can adjust the sensitivity threshold in the site settings.
* **Missing Token:** Ensure that you are using the built-in [Custom Liquid Tags](/docs/supported-liquid-tags), which handle the inclusion of the required captcha tokens automatically.