Currently, hCaptcha is the only available provider supported by Mastodon.
Other providers may be added in the future.
## hCaptcha
- Create a free hCaptcha account at [hcaptcha.com](https://www.hcaptcha.com)
- After completing registration, generate a Site Key and Site Secret from the hCaptcha dashboard
- Add the values to your Mastodon environment configuration as `HCAPTCHA_SITE_KEY` and `HCAPTCHA_SECRET_KEY`
- Restart the Mastodon services running on your server
- From the Mastodon web interface navigate to **Administration** > **Server settings** > **Registrations** and check the box labled "Require new users to solve a CAPTCHA to confirm their account"