Understanding reCAPTCHA: Purpose and Versions Explained

Online security is crucial for maintaining the integrity of your website and protecting your users. This article will explain the purpose of reCAPTCHA and the differences between reCAPTCHA v2 and v3.

reCAPTCHA and iDonate

When using iDonate, reCAPTCHA v2 and v3 are always enabled. When donors utilize your giving forms, they will be screened with v3 in the background and will only be presented with v2 additional challenges if the risk analysis flags the donation as suspicious.

What is reCAPTCHA?

reCAPTCHA is a free service provided by Google that helps protect websites from spam and abuse by distinguishing between human and automated access. By using advanced risk analysis techniques, reCAPTCHA blocks malicious bots while allowing legitimate users to access your site without unnecessary friction.

Purpose of reCAPTCHA

The primary purposes of reCAPTCHA are:

  • Preventing Spam: By filtering out automated bots, reCAPTCHA helps ensure that your contact forms, comment sections, and other interactive elements are used only by real users.
  • Protecting User Accounts: reCAPTCHA can be used on login pages to prevent brute-force attacks and unauthorized access attempts.
  • Enhancing Website Security: By blocking suspicious activities, reCAPTCHA adds an extra layer of security to your website, safeguarding both your site and its users.


reCAPTCHA v2 is the most widely used version and offers a straightforward, interactive experience to differentiate between humans and bots. 

  • “I’m not a robot” Checkbox - Users are presented with a checkbox to confirm they are human. Depending on the risk analysis, users might be prompted to solve an additional challenge, such as identifying images.

    reCAPTCHA v3

    reCAPTCHA v3 offers a more seamless and user-friendly experience by running entirely in the background. It doesn’t require any user interaction and assigns a risk score to each request.


    Donors might be prompted with additional reCAPTCHA v2 challenges for several reasons:

    • Suspicious Activity: If reCAPTCHA detects behavior that resembles automated activity, such as rapid clicks, frequent page reloads, or interactions that are too fast to be human, it may prompt for additional verification.

    • IP Address Reputation: Users accessing from IP addresses with a history of suspicious activity or associated with bot networks are more likely to be prompted with additional challenges.

    • Browser and Device Characteristics: Unusual browser configurations, outdated software, or unusual device characteristics can trigger reCAPTCHA to verify if the user is a human.

    • User Behavior: Irregular patterns in user behavior, such as excessive form submissions or abnormal navigation paths, can prompt reCAPTCHA to require further verification.

    • Geographical Location: Users accessing from regions with high rates of automated attacks may be subjected to additional challenges more frequently.

    • Cookies and Cache: If a user has disabled cookies or has a browser cache that suggests suspicious activity, reCAPTCHA might prompt for more verification.

    • Previous Interaction with reCAPTCHA: If a user has failed reCAPTCHA challenges multiple times before, the system might increase the difficulty of subsequent challenges.

    • Proxy Usage: Accessing the internet through a proxy, especially if the proxy is known for being used in fraudulent activities, can lead to more frequent reCAPTCHA challenges.