I read this about ReCaptcha:

  1. Unfortunately, as of 2011, some spammers appear to have figured out a way to bypass it, either through character recognition or by using humans. For that reason, it is not necessarily recommended.
  2. Part of the weakness of the ReCaptcha module is that ConfirmEdit doesn't include any penalty mechanism, so spam bots can simply keep trying to bypass the CAPTCHA until they get through. This is an issue that is strongly worth addressing in some way.
  3. Regardless of its strengths or weaknesses, reCAPTCHA can't be implemented on Wikimedia wikis because it produces a third-party dependency.

I need an alternative recommendation short of similar criticism to put in place of my ReCaptcha.

I do not want to pay any subscription or whatsoever.

  • That security issue is pretty easy to address (if that is accurate - I haven't confirmed that although I have used reCaptche quite a few times in my own projects) – Nick Wilde Feb 22 '14 at 10:23
  • Do you have a problem spam bots getting through your implementation? What other criteria do you have? "CAPTCHA that isn't this one" isn't really specific enough to give an informed recommendation for, this in currently just an alternatives search. – Caleb Feb 22 '14 at 10:27
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    @Any Body: Am I correctly reading that that you need it to be entirely on your own server rather than contacting any external server(s) for verification? – Nick Wilde Feb 22 '14 at 10:27