Fed up with Spam in your Wiki, Blog or Forum? All the CAPTCHA solutions you found are too difficult to implement or do not work on your shared hosting account? Captchator is the solution.
A CAPTCHA is a way to prevent automated web form submissions. You show the user an image with a confirmation code, and you only accept the submission if the user enters the code correctly.
To display the captcha image on your website, create an img tag that links to the Captchator server:
<img src="http://captchator.com/captcha/image/$yoursessionid" />
$yoursessionid, insert a unique string that identifies the session. You can
simply use a part of the PHP session ID or something similar for this.
Create or modify an existing form with a text field to send the captcha answer to your script.
Your script needs to check the submitted captcha answer for correctness. To do so, it loads the following URL from the Captchator server:
If the answer is correct, the result is "1", if not, it is "0".
http://captchator.com/captcha/image/(anything you like)and read the text from the picture.
http://captchator.com/captcha/check_answer/(anything you like)/(text from the picture). If you entered the text correctly, you will see "1".
Captchator is a hosted service, so you are probably wondering about its reliability. This can be answered easily: I am using Captchator on my own high-traffic websites www.mikrocontroller.net and www.ruby-forum.com, so it is in my own interest to keep it running.
Of course, I cannot make any guarantees. The service may be terminated at any time without prior notice, there may be outages and malfunctions. So far there have not been any, but you get the idea: use it at your own risk.
Many websites are already using captchator to protect forums, wikis, polls or comment forms from spam. Among them are websites based on PHP, Rails, Python, Coldfusion, Perl, ASP.net and other web frameworks. Below is only a small selection.