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Questions tagged [recaptcha]

For questions about the reCAPTCHA service: Designed to protect against spam and abuse by blocking bots while allowing valid users access.

reCAPTCHA is a system originally developed at Carnegie Mellon University that uses CAPTCHA to help digitize the text of books while protecting websites from bots attempting to access restricted areas.

reCAPTCHA requires a user to select images which do or don't include certain items in them. The technology works due the ability of a human being to distinguish subtle visual hints that AI would not yet recognize.

On September 16, 2009, Google acquired reCAPTCHA.

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Using reCAPTCHA on localhost

I'm developing a website using PHP and I want to make a human verification in one of the sessions. For the development, I'm initially running the system locally and when it is ready, I'm going to put it on some domain. In the reCAPTCHA website it is…
rlc
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How does Google reCAPTCHA v2 work behind the scenes?

This post refers to Google ReCaptcha v2 (not the latest version) Recently Google introduced a simplified "captcha" verification system (video) that enables users to pass the "captcha" just by clicking on it. But how can it differentiate a bot from a…
everlasto
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How to hide the Google Invisible reCAPTCHA badge

When implementing the new Google Invisible reCATPTCHA, by default you get a little "protected by reCAPTCHA" badge in the bottom right of the screen that pops out when you roll over it. I'd like to hide this.
James Law
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How to Reload ReCaptcha using JavaScript?

I have a signup form with AJAX so that I want to refresh Recaptcha image anytime an error is occured (i.e. username already in use). I am looking for a code compatible with ReCaptcha to reload it using JavaScript.
ahmet alp balkan
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Has reCaptcha been cracked / hacked / OCR'd / defeated / broken?

Have any programming methods have been used to defeat reCAPTCHA? I'm interested in seeing evidence and potentially demonstrations that reCAPTCHA in particular has been made obsolete by completely automated, humanless methods. To clarify, not looking…
Dave Rutledge
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How can I validate google reCAPTCHA v2 using javascript/jQuery?

I have a simple contact form in aspx. I want to validate the reCaptcha (client-side) before submitting the form. Please help. Sample code: <%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default2.aspx.vb" Inherits="Default2" %> …
Mahatma Aladdin
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How does this checkbox recaptcha work and how can I use it?

I've recently signed up to the oneplusone website https://account.oneplus.net/sign-up, and noticed this checkbox recaptcha How does it work, and how can I use it on my sites? Much better than those cryptic words/digits:) The recaptcha site does not…
Pedro Costa
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ReCaptcha API v2 Styling

I have not had much success finding how to style Google's new recaptcha (v2). The eventual goal is to make it responsive, but I am having difficulty applying styling for even simple things like width. Their API documentation does not appear to give…
jhawes
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How do I show multiple recaptchas on a single page?

I have 2 forms on a single page. One of the forms has a Recaptcha displaying all the time. The other should display a Recaptcha only after a certain event such as maxing out login attempts. So there are times when I would need 2 Recaptchas to…
oym
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reCAPTCHA ERROR: Invalid domain for site key

I have implemented my reCAPTCHA in line with as is shown in the example. I have this script in the head tag: In my form in HTML I have:
BlessedHIT
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Google Recaptcha v3 example demo

Until now, I was working with Google Recaptcha v2, but now I want to update my WebApp using the lastest version (v3). Is it possible to anyone add a fully working Google Recaptcha v3 example for a basic form as I can't find any working demos of…
Ommadawn
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How to check in js that user has checked the checkbox in Google recaptcha?

I have added the following before end of head I have added this before end of form
I can see the recaptcha similar to…
Hello Universe
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Change New Google Recaptcha (v2) Width

We've just started to implement the new google recaptcha as listed https://www.google.com/recaptcha/intro/index.html However the new method seems to be contained within an iFrame rather than embedded into the page thus making applying CSS more…
owenmelbz
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ReCaptcha 2.0: enable Submit button on callback if recaptcha successful

I have a very simple form as follows. I want to make it so that the Submit button is disabled, and only enabled after the user has successfully completed the ReCaptcha. I'm assuming I'm going to need some Javascript / jQuery to do this. Google's…
thanks_in_advance
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Validating Recaptcha 2 (No CAPTCHA reCAPTCHA) in ASP.NET's server side

The new Recaptcha 2 looks promising, but i didn't find a way to validate it in ASP.NET's server side, if(Page.IsValid) in This answer, is valid for the old Recaptcha, but not the new one, How to validate the new reCAPTCHA in server side?
Alaa Alweish
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