Captcha Verification (or Completely Automated Public Turing Test to tell Computers and Humans Apart) is a common web technique used to help ensure that your respondents are real humans and not a program written to spam your survey.

The respondent is asked to check a box to prove that they are human. If they succeed, they are allowed to continue to the next page of the survey. We recommend placing the CAPTCHA question on the first page of your survey, so that you can eliminate any fake respondents immediately, without a respondent being deducted from your volume.

In order to use CAPTCHA for surveys that use an own domain or are embedded (iframe) on your website, you must register the domains with Google’s reCATPCHA service. No respondent information is sent to Google as part of this service.

Here are some typical scenarios when using a CAPTCHA is a good idea:

• if you are offering an incentive and spreading a survey URL via social media.
• If you are embedding a survey in an iframe on a website (There re a lot of random bots that try to fill in any form found on the internet).
• If you are holding any type of voting.
• If you are holding an election, it is better to use the contacts system to insure that there is only one ballet per person. CAPTCHA does not stop someone from completing a survey twice.