Getting Started

Plain HTML Installation

The fastest way to get UCAPTCHA running — paste one script tag and every form on the page is protected automatically.

Step 1 — Get your site key

Log in to your UCAPTCHA dashboard, go to My Sites, and copy the site key for the site you want to protect. It looks like ucaptcha_live_xxxxxxxxxxxxxxxx.

Step 2 — Add the script tag

Paste the following snippet inside the <head> or just before the closing </body> tag of your HTML page. Replace YOUR_SITE_KEY with your actual key.

<script
  src="https://www.ucaptcha.site/captcha-widget.js"
  data-site-key="YOUR_SITE_KEY"
  defer>
</script>

That's it. UCAPTCHA will automatically detect every <form> on the page and inject the checkbox widget before the submit button.

Step 3 — Verify it's working

Load your page in a browser. You should see an "I'm not a robot" checkbox appear inside each form. Try submitting the form without checking it — the submission should be blocked with an error message.

Manual placement (optional)

If you want to control exactly where the widget appears, add an empty <div> with the data-ucaptcha attribute inside your form, and set data-auto-inject="false" on the script tag to disable automatic injection.

<form>
  <input type="text" name="name" placeholder="Your name" />
  <input type="email" name="email" placeholder="Your email" />
  <textarea name="message"></textarea>

  <!-- UCAPTCHA widget goes here -->
  <div data-ucaptcha></div>

  <button type="submit">Send message</button>
</form>

<script
  src="https://www.ucaptcha.site/captcha-widget.js"
  data-site-key="YOUR_SITE_KEY"
  data-auto-inject="false"
  defer>
</script>