Can Captcha Stop Bots from Accessing the Website?

can Captcha stop bots from accessing the websites
Can Captcha stop bots from accessing the websites

Most of the websites that you will visit nowadays on the internet will have this small pop-up menu that will either tell you to tick mark the “I am not a robot” checkbox or to solve the challenge in order to proceed ahead, and this type of security measure is called “Captcha”, that helps in protecting the website from unusual bot activities. Moreover, according to sources, at least 6,024,196 websites use Captcha as their go-to tool for website protection. Not to mention, according to, around 98% of the websites deploy reCaptcha instead of Captcha. But, if we keep these stats aside, can Captcha stop bots from accessing the websites?

Well, let’s try to answer that.


Can Captcha stop bots?

Yes, Captcha services can stop bots from entering the websites, as it is created to stop the automation process from being carried out. It asks every visitor to fill up the form according to the Captcha challenge that has been provided.

However, every single thing has its flaw, and it is applicable here too because as time has passed, AI and Bots have gotten much smarter and better in bypassing the Captcha challenges by using OCR tools, Captcha solving services, and other similar approaches. 

Therefore, one should not rely on a single protective service like Captcha, and should practice using other Bot management tools like Cloudflare Bot Management or Super Bot Fight Mode that can help in identifying “Bad Bots” without hindering the user experience.

How does Captcha work?

Classic Captcha which is still being used by many websites, asks the users or visitors to identify & rewrite the letters provided in the box. The letters which are provided by the Captcha bots are in a distorted form, and hence only humans can recognize them and pass the test, while bots fail to do so.

Although, with advanced machine learning, it has now become possible for a hacker to bypass these complex-looking images with the help of automated bots, Captcha solving services, and extensions. Thus, in the year 2009, Google introduced its advanced Captcha service called “reCaptcha” which is more advanced and secure than its former version.

How does reCaptcha work?

Well, to answer it simply, reCaptcha uses three different approaches to determine whether the user is a human or a bot, and they are:


This is the first approach that reCAPTCHA started using to differentiate between bots and humans.

Now, to explain it simply, this challenge provided users with text in image format, that was either derived from old newspapers, printed books, street addresses, or other real-world sources, which again was easy for humans but tuff for the bots. 

However, as they say, nothing is permanent and safe in this world, and so hackers started using the OCR technology to decipher image text into a simple text format that was recognizable by bots.

Image recognition:

In this type of reCaptcha challenge, a user is presented with 9 to 16 square images, which are needed to be identified according to the hints that are provided with this challenge.

Generally, this type of Captcha test is curated from a single image or parts of different images, and therefore it becomes very hard for a bot to determine which image is what. Even Artificial Intelligent programs struggle with it. To completely understand how image Captcha works, check out our practical guide.


In this type of reCaptcha challenge, a user is presented with a checkbox along with a message “I am not a robot”, where a user only needs to move his cursor towards the checkbox, and then click on it to bypass the Captcha challenge. Additionally, it also assesses the cookies as well as the internet history that is stored by the browser to tell if the user is a bot or a human being.

Further mentioning, this type of Captcha challenge examines the cursor movement of a user as it approaches the checkbox. As this cursor moment contains many tiny unconscious randomness, a bot can’t mimic it exactly, thus failing the test.

However, if the Captcha bot is unable to determine whether it is a bot or a human (which happens in rare cases), then as a part of an additional safety measure, it throws an Image Recognition Captcha test.

General user behavior assessment:

Lastly, this type or version of reCaptcha examines the user’s behavior as well as the history of interaction with the content on the Internet. In most cases, this approach doesn’t need anything extra, but if it is unable to determine human behavior, then it throws another Captcha challenge that is to be solved manually.

In what ways is the Captcha test triggered?

Captcha tests on a website are generally triggered in two ways: (1) Automatic, and (2) When it registers bot-like activity.

Can Captcha be bypassed?

Yes, a Captcha test can be bypassed using these methods.

What are the disadvantages of Captcha?

There are a few disadvantages of using a Captcha, and they are:

Bad user experience:

Who loves solving those annoying numbers, alphabets, or image puzzles, while surfing one’s favorite site?

No one right? 

So yes, a Captcha may protect your website from bot attacks, but your users may suffer. In fact, they would get so much frustrated, that they would actually leave the website for good, and never visit it again in the future. Moreover, it also wastes the precious time of the users.

Not suitable for visually impaired individuals:

The problem with authentic Captcha is that it relies solely on visual perception, and therefore it is similar to garbage for a partial as well as fully visually impaired individual.

Can be bypassed by bots:

Even though Captcha is improving at the security level on a day-to-day basis, hackers can easily find new ways to bypass the Captcha bots. Hence, creating an easy route for the bots to bypass and ruin the website.

Kills conversion rate:

Lastly, if you are using a Captcha service to protect your eCommerce or business website, then it may not come as handy.

For instance, whenever a customer encounters a Captcha challenge while checking out of your eCommerce website, he/she would only curse it and drop out of your website without purchasing that product. Hence results in a fall in conversion rate.

Final Remarks on “Can Captcha stop bots?”

So, after this discussion, we can clearly say that Captcha is meant to stop bots from interfering in internet-related operations.  However, it is not a foolproof solution to safeguard the online experience, and therefore it is much better to implement other forms of security measures on a website to prevent dangerous cyber security attacks.