Published: 03/11/2021

Impossible CAPTCHA

What are impossible CAPTCHAS?

An impossible CAPTCHA is a CAPTCHA that is different for each user, thus making it impossible to solve without human intervention. It’s an alternative to the classic CAPTCHA approach but maximizes effectiveness against spam bots by being completely unassailable by computer programs.

How an impossible CAPTCHA works

Impossible CAPTCHAs introduce a level of randomness into the generation process, making it impossible to write a computer program that can solve them all. To do so would require solving each unique CAPTCHA in order to make use of the solution.

Benefits of impossible CAPTCHAs

  • No need for a database of solutions. Any person solving the CAPTCHA will have to solve it from scratch, as they would compete in a challenge against another human.
  • Reduces hacking risks through smart obfuscation methods.
  • Allowing multiple solutions to one hard problem, increasing accuracy and solving time without compromising security.

Finding an impossible CAPTCHA service

An impossible CAPTCHA service requires randomness in its implementation to ensure they are not susceptible to brute force attacks. This randomisation is achieved by using software designed specifically for this purpose which generates customized images on the fly that change in every instance when displayed. An impossible CAPTCHA generator will generate a new image each time you load it in your browser, in order to ensure that only humans can attempt to solve the challenge presented by the website.

How humans solve impossible CAPTCHAs

Impossible CAPTCHAs are harder for humans than traditional ones but still easy enough to solve. They employ simple puzzles that are unique to each user, for example selecting the object out of five choices that doesn’t belong with the others or choosing which word is not like the others.

Impossible CAPTCHAs are more secure than standard ones as they make it harder on bots but still achievable by humans. This makes them an excellent choice for websites wishing to define what is and isn’t a computer program attempting to access it.

Why use impossible CAPTCHAs

Impossible CAPTCHAs force you to use your brain rather than just automatically trying every combination until victory presents itself. The barriers exist because these captchas can be solved only through human intelligence and effort, something that bots lack in abundance. It is a solution to the spam and hacking problems that tries to decompensate for the weaknesses of other security measures by adding another layer of security.

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