Popup mode

Verification appears in a modal when the user clicks. Best for sign-up and login forms. View source.

Live demo

Click the button, complete the verification in the modal, watch the token come back.

View HTML source SDK loader source Backend verify.php

Integration code

Copy these three pieces into your page.

<!-- 1. Load the SDK -->
<script src="https://cdn.captcha-cdn.net/captchala.js"></script>

<!-- 2. Add a trigger button -->
<button id="popup-btn">Verify</button>

<!-- 3. Initialize Captchala bound to the button -->
<script>
Captchala.init({
  appKey: 'YOUR_APP_KEY',
  product: 'popup',
  bindTo: '#popup-btn',
  action: 'login',
  lang: 'en',
  onSuccess: (res) => {
    // Send res.token to your backend (POST /verify.php).
    // Single-use; consume server-side, don't trust client.
    fetch('/verify.php', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ token: res.token, action: 'login' })
    }).then(r => r.json()).then(j => { /* j.ok === true */ });
  },
  onError: (err) => console.error(err)
});
</script>

When to use popup

Sign-up forms, login pages, password reset flows. Anywhere the user is already going to click a "Submit" or "Continue" button — bind the verification to that click and the user sees one modal, not a separate verification step.