«« Back

CAPTCHA: What is it? Do I need to use one on my website?

These are two very important questions that every website owner should ask themselves.

What is CAPTCHA?

A CAPTCHA is a test that websites can use in order to block ‘bots' (automated programs that repetitively spam a website with repeated submissions of various content). CAPTCHA's come in a variety of forms, some more effective than others.
  • Some are simple mathematical equations (ie. 1 + 1 = ?), or a simple checkbox. This is the first level of CAPTCHA tests to fail repeated ‘bot' attempts.
  • Most CAPTCHA tests use distorted alphanumeric images that humans can read, but machines and AI technology cannot. This can be frustrating for some users, however.
  • More recently a new type of CAPTCHA test has been put into use on some websites. This test is more complex and more difficult for machines to crack. It involves presenting a series of images to the user with an instruction such as, “Click all the images of street signs.” The user then selects any images with a street sign and clicks the submit button. Machines cannot easily perform this action, making these CAPTCHA tests more successful. This test is, however, also more difficult for humans to do as well, and may discourage some users from completing the test at all if an image was missed on the first attempt. Keep this in mind when selecting which CAPTCHA to use. Unless you are collecting information with a high risk of being targeted by bots, you probably don't need this level of the test.
It is important to keep accessibility in mind when implementing these tests. An audio version that is compatible with screen readers should be available for the visually impaired.

Do I need a CAPTCHA?

Not all websites are the same. They don't all have the same needs and they aren't all constantly under attack from malicious spam bots 24 hours a day. This article is not meant to scare you into believing this. Many websites don't require a CAPTCHA at all because they don't collect any form of information that can be spammed by a bot.

Which CAPTCHA should I use?

Does your website use a form of any kind to collect information from a customer?
  • If your answer is no, you probably do not need a CAPTCHA.
  • If your answer is yes, it is important to ask what type of information is being collected. A simple “Join Our Mailing List” form, probably doesn't require a CAPTCHA, and if it does use one just to be safe, the lowest level of the test is usually good enough. This low-level test is more friendly to the user and is less likely to deter a potential customer from entering their email address. This is very important to consider. Bots probably don't want your newsletter, but you do want your visitor's email. Don't chase them away with a complicated pictogram.
Does your website collect information in the form of a poll, or does your website have a pay-per-click system set up? A mid-level CAPTCHA may be a good idea if you want to ensure that all activity is performed by actual human beings, and not by automated machines.

Some websites collect sensitive or valuable information, or they affect how certain websites may rank in search engines and bots may be more likely to target these forms. In these cases, obtaining accurate information is likely important, so higher level CAPTCHA tests may be a good idea.

Some websites, only implement the use of a CAPTCHA test after an excessive number of attempts or submissions have been performed from a single IP address. This is a good option to consider, as it does not usually appear to the average user, so your customers are never inconvenienced.

As advancements are made in the area of AI technology, bots are getting smarter, and more complex CAPTCHA tests are becoming necessary, however. Please keep in mind that no test is 100% effective, but in many cases, bot activity can be prevented or reduced.

There are many other circumstances where a CAPTCHA may be recommended. These are only a few examples. This article is only meant to give you an idea of how to determine if you should use a CAPTCHA on your website. It is not meant to be a definitive guide on the subject. The best thing you can do if you aren't sure if you should use one of these tests is to ask your web development team.

We at Back2Front are happy to guide you through making these, and many other, decisions about your website. Your business matters to you and your website matters to us. Let us take the stress out of running your website.

We are Back2Front - The Website Management People!