A captcha,
without captcha

Keep away spam bots from your forms, without bothering your users.

A few lines of code, client and server side, and you are ready to go.

Use this public instance for free, or host your own Burnia.

What is Burnia?

Burnia is a simple script which permits you to easily identify spam bots, harvesters and other malicious agents crawling the web.

Contrary to the classic captcha, difficult and annoying to understand, Burnia evaluates the IP address of the user who wants to fill out your form and blocks any harmful sources: it is built on top of Project Honeypot, a global effort to monitor and index toxic sources on the Internet.

As easy as this!

How to use

Client side

In your form, add the row
<div id="burnia"></div>
and, at the beginning or at the end of the document, include the script
<script src="http://burnia.madbob.org/js/burnia.js"></script>

Server side

When the form is submitted, get the burnia-token parameter.

If it is missing or equal to "broken", do not accept the input.

Otherwise, call the endpoint
to ask for confirmation.

if (isset($_POST['burnia-token']) == false)

$burnia = $_POST['burnia-token'];
if ($burnia == 'broken')

$url = sprintf('http://burnia.madbob.org/check/%s', $burnia);
$confirmation = file_get_contents($url);
if ($confirmation != 'ok')


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