CAPTCHA twenty-two

As a frequent… OK obsessive, user of the web, I find myself increasingly exposed to the CAPTCHA; a trend that is beginning to get annoying.

Screenshot of the Google CAPTCHA

Googles CAPTCHA is not only more often than not difficult to read, its also inaccessible

A CAPTCHA may not be a term that you are immediately familiar with, but if you’re a web user I guarantee it’s something you’ll have had to contend with at some point.

It’s an acronym for ‘Completely Automated Public Turing test to tell Computers and Humans Apart’ – obviously. Still none the wiser? How about those annoying deliberately difficult to read images that you have to copy the text from before you can proceed to the next step – now you’ll recognise it!

Despite CAPTCHA being used on everything from Google Analytic to insurance quotes, the implementation of the technology sticks two fingers up to the most basic usability and accessibility guidelines.

What’s the issue

By their very nature CAPTCHAs are designed to stop current computer software from automatically reading and submitting content on webpages in order to limit activities that may result in the degradation or abuse an online service.

Of course it makes sense that you would want to implement measures that would inhibit such activity, but to what cost?

Aside from stopping automated software, I have on numerous occasion been baffled by the scrawl in front of me. Bewildered by the almost unrecognisable shapes some of the letter have taken on.

So while a user with good vision may struggle very occasionally, the task becomes a real challenge for a user with poor vision. Further still, most of the CAPTCHAs I’ve seen on the web aren’t compatible with assistive technologies such as screen readers, making them inaccessible.

So ultimately, sites using them run a significant risks of breaching DDA guidelines.

What’s the solution?

Screenshot of AOLs CAPTCHA

AOL provide their user with an accessible audio alternative

Despite the lack of evidence on most sites, there are accessible versions. These accessible CAPTCHAs provide exactly the same image style test, but with an option that allows the user to listen to an audio alternative. The audio means software like screen readers can play an audio file instead of trying (and failing!) to read the image.

The audio alternative can also help users with conditions such as dyslexia – which affects around 10% of the UK population, and it provides a usable alternative for anyone who struggles to make out the letters in the image.

With some companies such as AOL having already implemented the more accessible/usable version, it just begs the questions – Why aren’t all companies using them?

You can see more about accessible CAPTCHAs at

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