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Egglue Semantic CAPTCHA

Egglue Semantic CAPTCHA generates text CAPTCHA challenges for protecting websites from automated spam. Unlike conventional CAPTCHA, all challenges require only basic intuitive abilities to solve. The use of plain texts rather than images improves accessibility.

Below are examples of image CAPTCHAs (left) and Egglue Semantic CAPTCHA (right):

In the current Beta, visitors are presented with two meaningful sentences as plain texts, each missing one verb. Visitors are asked to type in the missing verbs so that the sentences make intuitive sense. An example challenge is:

Speakers can ______ sound.

A correct answer is play. Other correct answers include amplify, produce, control and others, as intuition suggests. Visitors are free to type in any verb as long as the completed sentences make intuitive sense. The CAPTCHA verification mechanism tries to accept all intuitively relevant solutions.


Egglue Semantic CAPTCHA provides a number of interesting advantages:

  • Better protected against automated recognition and spamming programs.
  • Better protected against human-based CAPTCHA breaking teams.
  • Accessible to visually impaired users.
  • Highly scalable.
  • Efficient CAPTCHA generation and verification.
  • More enjoyable for the user.
  • It's free! :-)

Learn more


CAPTCHA is often used to ensure that the visitor is human and not a machine. The main purpose of using CAPTCHA is to prevent automated spamming.

Like other CAPTCHAs, Egglue Semantic CAPTCHA is designed to prevent various kinds of web form spam, including:

  • Blog spam
  • Comment spam
  • Guestbook spam
  • Feedback form spam
  • Link spam
  • Wiki spam
  • Email form spam


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Feedbacks and suggestions are much welcome!

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