Web service API

When you sign up for your own account, you are provided with a unique API key. This key allows you to access the XML web service interface. For testing purposes you can use the API key "demo" which will serve a limited subset of questions.

A single CAPTCHA can be requested from the URL:


The XML response contains question and answer elements:

<question>If tomorrow is Saturday, what day is today?</question>

In the example XML, there are two permitted answers: "Friday" and "Fri". The MD5 hash of both (lower-case) answers are included. For an example of how to convert this XML into a form-based challenge, read how our service works.

How reliable is the service?

Uptime verified by Wormly.com

The service is provided from a European Amazon EC2 server which is monitored using the Wormly service. I don't provide an explicit SLA, but do my best to provide a completely reliable service.

Questions? Contact Rob.