We spend several hours every week conducting usability tests on a variety of different websites. In our research we often see people struggle with CAPTCHA, the anti-spam solution designed to differentiate between a human and a spambot. It’s easy to see why web teams adopt this tool to avoid spam – it is clearly an effective tool. However, they are probably not aware of how frustrating users find it! We regularly hear users say things like “oh I hate these things”, “not this thing again”, “why are they making it difficult for me?” In some cases we have seen users abandon a site altogether when faced with a CAPTCHA tool.
As a result of our observations we recommend that our clients remove the CAPTCHA tool from their site. In a recent client meeting we had a long discussion about the UX implications of anti-spam tools, and they challenged us to find a better alternative, that protected them from spam but didn’t frustrate users in the process. We accepted that challenge and thought we’d share the findings with our readers. In reverse order, we provide our top 5 CAPTCHA alternatives.
Starting at number 5 is an alternative to CAPTCHA that still slows people down, but incorporates a bit of fun into the process. This approach typically asks users to drag and drop items to prove they are human.
Making anti-spam into a game could allow the web team to complement the existing brand language. So for example a car brand could set up a game where users have to drag different car parts to build a car. Whilst we like the idea of turning spam prevention into a fun game, it still interrupts users from completing a simple task to submit a form. In some cases they can take some time to complete and in many contexts we would be concerned about how users would react to this tool. For example, we can’t imagine a financial analyst being too impressed with having to ‘plant a garden’ to access a financial report.
4. Simple questions
The next alternative would be to ask users to respond to a simple question. These questions are designed to differentiate humans from spambots. This is a popular alternative that we have seen work quite well, using either a simple maths question (see below) or a simple general knowledge question (i.e. “What colour is the sky?”)
This CAPTCHA alternative is simple to implement, it’s effective, and it can allow companies to add humour or a brand voice to the trivia questions. However, this option should still be considered carefully to ensure accommodation is made for users of varying learning abilities and cultural backgrounds. As with many of these solutions, not all users will understand why they are being asked these questions and this can lead to frustration. A contextual help link to explain why they are being asked this, could alleviate the issue.
The slider tool uses the simple interaction of clicking on a button and sliding it from left to right to validate the user as human. The tool works because the task is easy for humans to complete while the tool remains invisible to spambots.
This is a simple interaction that is likely to be familiar to iPhone or iPad users that need to ‘slide to unlock’ their device. With the example shown above, users might be led to believe that swiping the slider will submit the form, when in reality it just activates the button. A better option here would be to amend the instruction to ‘slide to activate the send button.
The check box option works by placing a check box or radio button on a form that users are asked to select or unselect before submission. Again, this is a simple interaction, and in the context of web forms, checkboxes are commonplace so users should be able to complete it quickly without too much thought.
The simplicity of this option means it rates highly on our list of CAPTCHA alternatives. Our only hesitation would be to make sure the terminology is easy for users to understand. ‘I’m not a spambot’ is likely to confuse users who don’t know what a spambot is. We would recommend ‘I am a human’ with a contextual help link (i.e. ‘Why am I being asked this?’) next to the check box. Alternatively to eliminate any confusion to users, do not mention the fact it’s a spam detection tool and simply label ‘Select this box before pressing submit’.
1. Honeypot or time-based forms
The best alternative to a CAPTCHA tool is to completely remove the requirement for users to ‘prove they are human’. Two examples we found are the honeypot or time-based alternatives.
The honeypot solution works by placing a hidden field in a form that the spambot would see, but users wouldn’t. The idea is that spambots will recognise it as a normal field to complete and any forms with an entry will be flagged as spam.
Another technical alternative which is hidden from users is the time-based form. The idea behind this is to detect a spambot based on the time it takes to complete a form. Genuine users take a few moments to complete a form, whereas spambots complete forms instantly. Therefore any forms submitted too quickly would be identified as a bot. We can see this solution working quite well, as long as the time-frame set is practical for users to achieve.
There are a number of alternatives to CAPTCHA available. However, like any change to a website, it is important to consider the impact the tool will have on users before it is implemented. There are a number of technical considerations with these alternatives that we have not discussed here. We would therefore recommend any team considering CAPTCHA alternatives should consult with UX and technical consultants before making a decision. The best approach would be to narrow down the options and conduct user tests to select the best option.
- Users hate using sites with CAPTCHA
- Alternative solutions are available which are not as frustrating as CAPTCHA
- The best solutions are those that don’t require users to prove they are not spambots
Are you using an alternative CAPTCHA solution? If so, get in touch for some tips on how you could test it with your users.