An Accessible CAPTCHA Chad Killingsworth Web Projects Coordinator

Office or Department What is a CAPTCHA? Completely Automated Public Turing test to tell Computers & Humans Apart

Office or Department Examples Hotmail: Blogger:

Office or Department What’s the Purpose?  Prevent Spam Do They Really Work?  Missouri State 404 Error Submission Example

Office or Department What’s the Problem?  Most CAPTCHAs are solely visual – easier to implement  Completely unusable by the blind  Can cause problems for the color blind

Office or Department How to Make a CAPTCHA Accessible  Include an audio test

Office or Department Implementation  Text-to-speech synthesis – read the visual CAPTCHA  Separate test – user enters a word or series of numbers they hear

Office or Department Missouri State Example

Office or Department Implementation Details  Pre-generate test samples – does not require the server to do text-to-speech  Correct numbers require the ability to determine context

Office or Department When to Use a CAPTCHA  Public forms only – make campus only forms restricted

Office or Department References  The CAPTCHA Project  Standards Schmandards

Office or Department Questions