Null CAPTCHA

Test the behavioral analysis demo below.

Connection Error: Could not connect to Null CAPTCHA server. Please verify the server is running on port 3000.
I'm not a robot
Behavioral AI

Developer Integration Guide

Integrate Null CAPTCHA into your own application in 4 simple steps:

1. Include the Client Script

Add this script tag in your HTML <head> or body:

<script src="https://null.dill.moe/js/null.js" async defer></script>

2. Create a Container Element

Place a placeholder div where you want the captcha widget to render:

<div id="null-captcha-widget"></div>

3. Render the Widget

Initialize the captcha in JavaScript once the script loads:

window.addEventListener('load', () => {
    window.NullCaptcha.render('null-captcha-widget', {
        onSuccess: (token) => {
            // Verification succeeded! Send token to your backend
            console.log("Verified. Token:", token);
        },
        onFailure: (err) => {
            console.error("Verification failed:", err);
        }
    });
});

4. Validate on Backend

From your server, verify the token by making a POST request:

// Request
POST https://null.dill.moe/api/validate
Content-Type: application/json
{ "token": "timestamp.score.nonce.signature" }

// Success Response
{ "success": true, "score": 1.0 }