CAPTCHA – Passing the Problem to the User

CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) is a method of preventing spam commonly used in web forms. The user is displayed a distorted image of numbers, letters or words and asked to type them out. This ensures that the form is not filled out automatically by a bot and reduces the spam sent through that form.

It is clear that this solution goes a long way to dealing with the spam problem and the webmaster is happy, but at what cost to the user? At best there is another field to fill out. At worst, if the image is hard to read or the user has some visual impairment it is a barrier for the user to completing the form.

Most good CAPTCHA implementations will include a visual (image with text) and audible (audio playback of the text) meaning that even those struggling to read the image will be able to complete the form. There are also usually options to “refresh” the image, creating a potentially easier to read image.

All of this helps but does not avoid the fact that the user is having to do more work to complete the form. We are always looking to increase conversions and should be looking at reducing the actions a user has to do (such as avoiding duplicate email and password fields) in order to increase the chance they will fill out the form.

So what about alternatives? A great example of spam detection is the excellent Akismet as popularised by WordPress. Spam is automatically detected by algorithms and tests on the Akismet server and this reduces manual checking to pretty much zero as well as leaving the user experience untouched.

So a use of Akismet or similar service is the ideal solution – the user does not see a change and the spam problem is still solved. The service should err on the side of caution, to prevent losing genuine information. Regular checks of the “spam” content should also be considered.

The second best solution, which can also be used in conjunction with an Akismet type integration, would be to improve your admin systems. If your form is submitting directly to email then it will be difficult to check and remove large amounts of spam. Having a tidy admin area with the ability to view/edit/delete data all together will reduce time spent on checking for spam.

Many CAPTCHA implementations are unnecessary and are done as either habit or due to some idea that it is a professional thing to do – question whether you will actually receive spam and is it better to deal with it manually?

The final alternative would be to make the CAPTCHA less obtrusive, more fun or easier in some creative way. Microsoft have the initiative ASIRRA which shows promise – the user is asked to identify pictures of dogs and cats. A simple click by the user is all that is needed and in tests many found the exercise fun.

Some websites also offer simple random questions (e.g. what is 3 plus 5?) although these are potentially circumvented as well as lacking the fun appeal to most users.

In conculsion I stress that you should consider first and foremost whether you need spam protection. If you need to, try to ensure the spam protection does not intrude on the users experience – your conversion rates will reward you.

Do you have any CAPTCHA tips, tricks, advice or questions? Get involved and comment below!

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Carey

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