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What is a Form CAPTCHA?

By September 12, 2019November 18th, 2019E-Commerce, Google, Website Design and Hosting

A CAPTCHA, Completely Automated Public Turing Test to Tell Computers and Humans Apart, is a type of Human Interaction Proof (HIP) that distinguish between computers and humans.  CAPTCHAs are a type of challenge-response test that are typically seen on website forms or surveys to reduce spam.  Computers are able to automatically fill out forms and captchas force the respondent to enter a word or combination of words before they are able to submit successfully. 

Types of Form CAPTCHAs

Form CAPTCHA illustrationFor actual human beings these tests are simple and straight forward, but for a computer they are nearly impossible to solve.  CAPTCHA applications are designed to present a different CAPTCHA to different users; otherwise it wouldn’t take spammers long to spot the form, decipher the letters, and program applications to type the correct answer automatically.  In the nineties, the most common CAPTCHA is an image of distorted letters.  If the letters are typed correctly into the field and matched the ones from the distorted image then you have passed the test.  More recent CAPTCHAs display an image with a grid on top and users will be asked to identify all areas of the grid containing a certain feature (such as store sign or parked car).  Some CAPTCHAs are also presented as simple sums, like 5+1, or audio for vision impaired users.

Google Offers reCAPTCHA

Google started offering a free service called reCAPTCHA that protects your website from spam and abuse.  According to Google, uses an advanced risk analysis engine and adaptive challenges to keep automated software from engaging in abusive activities on your site. It does this while letting your valid users pass through with ease.  It which a little more inquisitive than the original CAPTCHA.  The most recent CAPTCHA helps you detect abusive traffic on your site without any user friction.  It returns an interaction score with your website and provides you more flexibility to take appropriate actions. 

reCAPTCHA recognizes that some people get tired of filling in CAPTCHA forms and deems if their behavior on the site is human-like or not.  If the actions are deemed humanly then reCAPTCHA won’t serve a complete CAPTCHA test, it will simply ask the users to tick a box to confirm “I am not a robot.”  However, if the users behaviors are deemed more robotic like in nature then a more complicated CAPTCHA test will be served.

Benefits of a Form CAPTCHA

Obviously the main benefit of a CAPTCHA on your website forms are detecting hackers and blocking robotic software from submitting fake requests.  In addition CAPTCHAs:

  • Protect the integrity of online polls or surveys by stopping robots from submitting false responses that could skew your results.
  • Suspend brute force attacks from hackers trying to login to specific accounts repeatedly trying to use different password combinations.
  • Prevent hackers from creating multiple email accounts that they could possibly use for criminal reasons.
  • Cease spammy comments on blogs or content pages linking to other websites.
  • Prevent people from buying several tickets to highly praised events for resell purposes.
  • Secure online shopping.


Adding a CAPTCHA to your website has become standard in this day of age.  If you have been experiencing false website submissions or spammy comments, contact SIDEKICK for assistance in installing a form CAPTCHA.

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