captcha.eu

Captcha.eu


After much research, I came to the conclusion that captcha.eu is the best captcha solution for inside the EU. It also offers some nice spam protection outside regular form protection! I highly recommend it.


Best captcha plugin with great support

Captcha.eu, the GDPR compliant captcha plugin for WordPress!

Adam Greenwell

Guard Dog is a focused WordPress security plugin for the login door, authentication, sessions, and practical access workflows. With custom login URLs, two-factor authentication, passkeys, CAPTCHA providers, access control, and activity logging, Guard Dog helps site owners tighten the parts of WordPress that get bothered most.
Key Features:
<ul>
<li>Custom Login URLs – Hide your wp-admin and wp-login.php from attackers</li>
<li>Two-Factor Authentication (2FA) – TOTP-based authentication with recovery codes</li>
<li>Social Login (OAuth) – Sign in with Google, Microsoft, or Apple</li>
<li>Passkeys – Use device-based biometric authentication like Face ID, Touch ID or Windows Hello</li>
<li>Multiple CAPTCHA Providers – Support for Google reCAPTCHA v2/v3, hCaptcha, and Cloudflare Turnstile</li>
<li>Login Attempt Limiting – Prevent brute-force attacks with intelligent lockout</li>
<li>Access Control – IP-based whitelist/blacklist protection</li>
<li>Activity Monitoring – Comprehensive logging of security events</li>
<li>Temporary User Access – Create temporary WordPress users with time-limited, secure access</li>
<li>Frontend Account Security – Shortcodes and blocks for login, passkeys, 2FA, and session controls</li>
</ul>
Why Choose Guard Dog?
<ul>
<li>Privacy-Focused – Multiple CAPTCHA options including privacy-first providers</li>
<li>WordPress.org Compliant – Built following WordPress coding standards</li>
<li>Site-Owned Controls – No central cloud platform required for core protections</li>
<li>User-Friendly – Intuitive interface with helpful documentation</li>
<li>Regular Updates – Actively maintained and updated</li>
</ul>
Perfect For:
<ul>
<li>Business websites requiring enhanced security</li>
<li>WordPress sites handling sensitive data</li>
<li>Multi-user sites with complex access requirements</li>
<li>Anyone wanting practical login and account protection without a central SaaS dependency</li>
</ul>
Frontend Shortcodes:
<ul>
<li><code>[guard_dog_login_form]</code> renders a public Guard Dog-managed login form</li>
<li><code>[guard_dog_passkey_login]</code> renders a standalone passkey sign-in button for custom login pages</li>
<li><code>[guard_dog_two_factor]</code> renders logged-in 2FA management</li>
<li><code>[guard_dog_passkeys]</code> renders logged-in passkey management</li>
<li><code>[guard_dog_sessions]</code> renders logged-in active-session management</li>
<li><code>[guard_dog_account_security]</code> renders the composite logged-in account security widget for 2FA, passkeys, and sessions</li>
<li><code>[guard_dog_2fa]</code> remains supported as the legacy alias for the account security widget</li>
</ul>
Block-based themes can use the matching Guard Dog Login Form, Passkey Login, Two-Factor Auth, Passkeys, Sessions, and Account Security blocks.
<h3>Additional Information</h3>
Support: 
For support questions, please use the WordPress.org support forums.
Privacy: 
Guard Dog respects user privacy and offers multiple privacy-focused options. Third-party services are only contacted when you enable features that need them, such as CAPTCHA, email delivery, social login, IP reputation, or geolocation.
Security: 
Guard Dog follows WordPress security best practices. User input is sanitized and output is escaped throughout the plugin.
<h3>Third-Party Services</h3>
Guard Dog integrates with the following third-party services to provide CAPTCHA protection. These services are optional and only used when CAPTCHA features are enabled.
<h3>Google reCAPTCHA (v2 and v3)</h3>
What it is: Google’s CAPTCHA service that helps protect websites from spam and abuse.
What it’s used for: 
– Verifying that login, registration, and password reset attempts are made by humans 
– Preventing automated bot attacks on your WordPress forms
What data is sent and when: 
– User interaction data (mouse movements, time spent on page) when CAPTCHA is solved 
– IP address of the user 
– Site domain for verification 
– CAPTCHA response token
Privacy and Terms: 
– <a href="https://policies.google.com/privacy" rel="nofollow ugc">Google reCAPTCHA Privacy Policy</a> 
– <a href="https://policies.google.com/terms" rel="nofollow ugc">Google reCAPTCHA Terms of Service</a> 
– <a href="https://developers.google.com/recaptcha/docs/v3#data_usage" rel="nofollow ugc">Google reCAPTCHA Data Usage</a>
<h3>Cloudflare Turnstile</h3>
What it is: Cloudflare’s privacy-first CAPTCHA alternative that doesn’t require user interaction.
What it’s used for: 
– Invisible verification of human users during login, registration, and password reset 
– Privacy-focused protection without tracking or cookies
What data is sent and when: 
– Non-interactive browser signals when forms are submitted 
– IP address for verification 
– Site domain for validation
Privacy and Terms: 
– <a href="https://www.cloudflare.com/privacypolicy/" rel="nofollow ugc">Cloudflare Privacy Policy</a> 
– <a href="https://www.cloudflare.com/terms/" rel="nofollow ugc">Cloudflare Terms of Service</a> 
– <a href="https://developers.cloudflare.com/turnstile/" rel="nofollow ugc">Turnstile Documentation</a>
<h3>hCaptcha</h3>
What it is: A privacy-focused CAPTCHA service that doesn’t track users across websites.
What it’s used for: 
– Human verification during login, registration, and password reset forms 
– Privacy-conscious alternative to Google reCAPTCHA
What data is sent and when: 
– User interaction with CAPTCHA challenge 
– IP address for verification 
– Site domain for validation
Privacy and Terms: 
– <a href="https://www.hcaptcha.com/privacy" rel="nofollow ugc">hCaptcha Privacy Policy</a> 
– <a href="https://www.hcaptcha.com/terms" rel="nofollow ugc">hCaptcha Terms of Service</a> 
– <a href="https://www.hcaptcha.com/data-processing" rel="nofollow ugc">hCaptcha Data Processing</a>
<h3>Google OAuth (Social Login)</h3>
What it is: Google’s OAuth 2.0 service that allows users to sign in using their Google account.
What it’s used for: 
– Authenticating WordPress users via their Google account 
– Retrieving basic profile information (name, email) to link or create accounts
What data is sent and when: 
– User is redirected to Google’s authorization server when clicking “Sign in with Google” 
– An authorization code is exchanged for an access token on your server 
– Basic profile information (name, email, Google user ID) is retrieved from Google’s API 
– No ongoing data sharing – data is only retrieved during the login process
Privacy and Terms: 
– <a href="https://policies.google.com/privacy" rel="nofollow ugc">Google OAuth Privacy Policy</a> 
– <a href="https://policies.google.com/terms" rel="nofollow ugc">Google OAuth Terms of Service</a> 
– <a href="https://developers.google.com/terms/api-services-user-data-policy" rel="nofollow ugc">Google API Services User Data Policy</a>
<h3>Microsoft Azure AD (Social Login)</h3>
What it is: Microsoft’s OAuth 2.0 service via Azure Active Directory that allows users to sign in using their Microsoft account.
What it’s used for: 
– Authenticating WordPress users via their personal Microsoft account or organizational (work/school) account 
– Retrieving basic profile information (name, email) to link or create accounts
What data is sent and when: 
– User is redirected to Microsoft’s authorization server when clicking “Sign in with Microsoft” 
– An authorization code is exchanged for an access token and ID token (JWT) on your server 
– Basic profile information (name, email, Azure object ID) is extracted from the ID token 
– No ongoing data sharing – data is only retrieved during the login process
Privacy and Terms: 
– <a href="https://privacy.microsoft.com/en-us/privacystatement" rel="nofollow ugc">Microsoft Privacy Statement</a> 
– <a href="https://www.microsoft.com/en-us/servicesagreement" rel="nofollow ugc">Microsoft Services Agreement</a> 
– <a href="https://learn.microsoft.com/en-us/entra/identity-platform/" rel="nofollow ugc">Microsoft Identity Platform Documentation</a>
<h3>Apple Sign In (Social Login)</h3>
What it is: Apple’s OAuth 2.0 / OpenID Connect service that allows users to sign in using their Apple ID.
What it’s used for: 
– Authenticating WordPress users via their Apple ID 
– Retrieving basic profile information (name, email) to link or create accounts
What data is sent and when: 
– User is redirected to Apple’s authorization server when clicking “Sign in with Apple” 
– An authorization code is exchanged for an access token and ID token (JWT) on your server 
– Basic profile information (email, user ID) is extracted from the ID token 
– User’s name is only provided on first authorization; subsequent logins return only the user ID 
– Apple may provide a private relay email address instead of the user’s real email 
– No ongoing data sharing – data is only retrieved during the login process
Privacy and Terms: 
– <a href="https://www.apple.com/legal/privacy/" rel="nofollow ugc">Apple Privacy Policy</a> 
– <a href="https://developer.apple.com/sign-in-with-apple/get-started/" rel="nofollow ugc">Sign in with Apple Guidelines</a> 
– <a href="https://developer.apple.com/terms/" rel="nofollow ugc">Apple Developer Program License Agreement</a>
<h3>TOTP (Time-based One-Time Password) Standard</h3>
What it is: An open standard (RFC 6238) for generating time-based one-time passwords used in two-factor authentication.
What it’s used for: 
– Generating secure, time-limited authentication codes for 2FA 
– Providing backup authentication when primary 2FA methods are unavailable 
– Enabling compatibility with popular authenticator apps (Google Authenticator, Authy, Microsoft Authenticator, etc.)
What data is sent and when: 
– No external data transmission – TOTP codes are generated locally using the TOTP algorithm 
– Secret key generation – A unique secret key is generated locally when 2FA is enabled for a user 
– QR code generation – QR codes are generated locally for easy setup with authenticator apps 
– Code verification – Generated codes are verified locally against the stored secret key
Privacy and Terms: 
– <a href="https://tools.ietf.org/html/rfc6238" rel="nofollow ugc">RFC 6238 – TOTP Standard</a> 
– <a href="https://policies.google.com/privacy" rel="nofollow ugc">Google Authenticator Privacy Policy</a> (if using Google Authenticator app) 
– <a href="https://authy.com/privacy/" rel="nofollow ugc">Authy Privacy Policy</a> (if using Authy app) 
– <a href="https://privacy.microsoft.com/en-us/privacystatement" rel="nofollow ugc">Microsoft Authenticator Privacy Policy</a> (if using Microsoft Authenticator app)
<h3>Data Handling Summary</h3>
When CAPTCHA is disabled: No data is sent to any third-party services.
When CAPTCHA is enabled: Only the specific provider you choose receives verification data. Data is not shared between providers or stored by Guard Dog beyond the verification process.
When 2FA is disabled: No external data transmission occurs.
When 2FA is enabled: 
– All TOTP operations (code generation, verification) happen locally on your server 
– No data is transmitted to external services for 2FA functionality 
– Authenticator apps only receive the initial setup QR code or secret key 
– Recovery codes are generated locally and stored securely
When Social Login is disabled: No data is sent to any OAuth provider.
When Social Login is enabled: 
– Data is only sent to the configured providers (Google, Microsoft, Apple) during the login process 
– Only basic profile information (name, email, user ID) is retrieved 
– Social account links are stored locally in your WordPress database 
– Users can unlink their social accounts from their profile at any time
User control: Users can choose which CAPTCHA provider to use, or disable CAPTCHA entirely. 2FA can be enabled/disabled per user, and users can choose their preferred authenticator app. Social login can be enabled/disabled by administrators, and users can manage their linked social accounts. All security features are optional and configurable.

Guard Dog

Plugin-first WordPress login and account security with custom login URLs, 2FA, passkeys, CAPTCHA protection, access control, sessions, and activity lo …

Captcha.eu vs Guard Dog