Having a CAPTCHA is Killing Your Conversion Rate

Posted by tallen1985

SEOs can occasionally find ourselves guilty of focusing on just the following few things:

  1. Links
  2. Rankings
  3. Fun cuddly animals that Google keeps releasing from its algorithmic zoo

Quite often we are heard muttering that user experience isn’t really our problem. We are all about the above three points. However, as the job of SEOs continues to become broader, requiring a greater number of skill sets, I think user experience is something we can all work on. Besides, surely if we focus some of our energy on this, we are going to end up with much happier users, which in turn will result in higher conversions.

There are various ways to work on improving user experience, and of course, conversion rate optimization also plays a part. Today, I want to focus on one specific part of user experience — CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) — and why I think they suck.

CAPTCHAs ask frustrating questions

When you encounter a CAPTCHA, you are being asked the question,”Are you a robot?” It’s like asking a customer who is about to enter a physical store, “Are you a thief?” before you allow them to walk through the door. So we used to flood our users with these “questions:”

And from there we have now moved to this:

Literally every time I see one of the above it makes me wish that this was on a nearby wall:

CAPTCHAs act as a barrier between you and your customers

Back in 2009, Casey Henry wrote a great post on CAPTCHA’s effect on conversion rates. He highlighted the fact that with CAPTCHA turned off, a company’s conversion rate would increase by up to 3.2%. It’s worth noting that the CAPTCHA type used in this test was based on the more traditional word format. That 3.2% is a pretty big potential gain for a whole lot of companies.

Traditional Word Format CAPTCHA

CAPTCHAs are not a solution, they are a problem

At the beginning of 2013 it was announced that Ticketmaster was finally ditching its traditional CAPTCHAs. Ticketmaster proceeded with an alternative system by SolveMedia. The system presents users with an image or video, the user then has to type a phrase associated with that image. In the video version of the product, a descriptive phrase will appear which the user then has to copy into a box below. If they are not willing to do this, they need to watch the video for a certain amount of time (similar to YouTube advertising) before continuing.

Right now, companies are producing variations of novelty products aimed at helping us to stop spam from landing in our inboxes. Many products claim they are aimed at improving the user experience by making this easier for humans. They come in a variety of styles, ranging from completing a simple sum to those that are image-based or even gamifying CAPTCHAs (such as Are You Human).

Yet all of these “solutions” create the same problem. I, the user, am trying to complete a purchase, fill in a form, or even just submit a comment. And you, the website, keep putting this frustrating technological barrier between myself and my goal, just so you don’t have to sort through a few items of spam.

Another major concern is that these products aren’t particularly user-friendly for those who are blind or partially sighted. Some simply offer the same audio CAPTCHAs (and problems) that we have been experiencing for as long as we remember.

CAPTCHA is built for advertising, not users

The key difference for me with image-based products such as SolveMedia and Minteye is that they seem to act as another opportunity to push an advert in front of users. In some cases they force you to watch an advert just to progress to the next page.

Users don’t want to see adverts even when they are “subtly” placed around a beautifully designed page. Yet, more and more we are moving away from giving the user a choice about viewing an advert to the point where adverts are forced upon them (ahem…YouTube).

So people must be ditching CAPTCHA, right?

Despite statistics like those shared by Casey Henry, the fact is that the use of CAPTCHA is actually on the increase. Perhaps for many webmasters this is just becoming common practice, almost the norm. After all, it’s a quick fix that means we, as webmasters, no longer have to worry about dealing with spam.

Figures from Drupal’s usage statistics show that they alone have nearly 200,000 people using one of their variants of CAPTCHA. This is a barrier to a more fulfilled user experience that doesn’t seem to be going away.


“CAPTCHAs are designed to be easy for humans but hard for machines”

…according to a study carried out by Stanford University into the use of CAPTCHA by humans. Yet, by testing more than 1,100 people, gathering 11,800 completed surveys, and studying 14,000,000 samples from a week’s worth of data from eBay, they revealed just how difficult CAPTCHA has become for humans.

The study showed that, on average:

  • Visual CAPTCHAs take 9.8 seconds to complete
  • Audio CAPTCHAs take much longer (28.4 seconds) to hear and solve
  • Audio CAPTCHA has a 50% give-up rate
  • Only 71% of the time will 3 users agree on the translation of a CAPTCHA
  • Only 31.2% of the time will 3 users agree on the translation of an audio CAPTCHA

With around 1% of the audience currently using audio CAPTCHA, this is potentially a huge market to lose.

So what is the solution?

There is a time and a place for CAPTCHA. For some sites, it may be unavoidable. However, any solution that is extremely effective rapidly becomes widely used, and as such, becomes a target for hackers.

There are some really simple solutions already out there that will help to reduce the amount of spam you receive but won’t interfere with your user experience.


Akismet provides an effective defence that has no impact upon your users. It comes as a variety of plugins and is generally easy to implement on your site. Akismet monitors millions of sites, constantly learning new methods to beat comment spam.

The honeypot technique

Essentially, the honeypot technique is used to hide a field on a form from the user. If this field is then filled in, the chances are pretty high it was by a machine. The major downside to this method is that the form could be accidentally completed by a visually impaired user. Therefore, it might be useful to also label the field with something such as, “If you are human, don’t fill in this field”.

We still ultimately have the problem that whatever we do to ensure a user doesn’t fill in the form, a malicious script could perform its own interpretations by learning which labels mean that a field should be left alone.

However, the key benefit to this method is that the user isn’t getting punished by being asked to complete something that is irrelevant to their actions.

Is it time you ditched your CAPTCHA?

I think we need to focus on what creates a better experience for users by asking ourselves the following questions:

  • Is the amount of spam you are receiving really worth potentially losing conversions?
  • If the answer is yes, is your CAPTCHA friendly to all users, including those who are visually impaired?
  • CAPTCHAs are for robots, not for humans. Unfortunately, anything one person can code to try and prevent robots from entering a site is something another can find a way through. The real consideration is, are we just shoving our problem with spam onto our customers?

When it comes down to it, CAPTCHAs lead to a negative experience on our sites. They frustrate users, damage conversion rates, and they are not particularly friendly to visually impaired users. Most of all, it is shifting our problem onto our users. That’s definitely not right. Getting rid of CAPTCHAs will not only improve our users’ experiences, but it will also improve the web as a whole. This should be the beginning of the end of the CAPTCHA. If you have a CAPTCHA, I urge you to remove it now!

What do you think?

Image credits




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