checkify

Checkify helps WordPress site owners reduce CAPTCHA friction by using privacy-first human verification.
Instead of asking visitors to solve puzzles, Checkify lets visitors complete a verification flow and return a verification result to the WordPress site. This can be used on pages, forms, or custom flows where the site owner wants to request human verification or age verification.
Checkify is designed around privacy-first verification. The WordPress site receives a verification result, not unnecessary personal identity data.
<h4>Features</h4>
<ul>
<li>CAPTCHA alternative for WordPress</li>
<li>Privacy-first human verification</li>
<li>Age verification profiles (18+, 21+, 25+)</li>
<li>Site connection using a QR code</li>
<li>Local QR rendering in the browser</li>
<li>Shortcode support using [checkify_verify]</li>
<li>Live Checkify API integration</li>
<li>No external QR code generation service</li>
</ul>
<h4>How it works</h4>
<ol>
<li>Install and activate the Checkify plugin.</li>
<li>Open the Checkify settings page in WordPress.</li>
<li>Generate a connection QR code.</li>
<li>Scan the QR code in the Checkify app to connect your WordPress site.</li>
<li>Copy your Checkify Pass ID and paste it into the plugin settings.</li>
<li>Add [checkify_verify] to the page where you want to show human verification.</li>
</ol>
The shortcode creates a verification request, renders a QR code locally in the visitor’s browser, polls for verification status, and stores a temporary local verification result for that visitor.
<h3>External services</h3>
This plugin connects to Checkify services to provide human verification.
Service used:
<ul>
<li>Checkify API: https://checkify.me</li>
<li>Checkify website: https://checkify.me</li>
</ul>
The plugin connects to Checkify when:
<ul>
<li>A site administrator creates a site connection claim.</li>
<li>A site administrator polls the status of a site connection claim.</li>
<li>A connected WordPress site creates a verification request.</li>
<li>A connected WordPress site checks the status of a verification request.</li>
<li>A connected WordPress site confirms a completed verification result.</li>
</ul>
The plugin may send the following data to Checkify services:
<ul>
<li>The WordPress site domain.</li>
<li>A Checkify site identifier.</li>
<li>A Checkify installation identifier.</li>
<li>A Checkify Pass identifier configured by the site administrator.</li>
<li>Verification request identifiers.</li>
<li>Verification status tokens.</li>
<li>Request timestamps.</li>
<li>Cryptographic signatures used to authenticate the WordPress installation.</li>
</ul>
The plugin does not use an external QR code generation service. QR codes are generated locally in the visitor’s browser using the bundled QRCode.js library.
Checkify privacy policy: https://checkify.me/privacy-policy
Checkify terms: https://checkify.me/terms_and_conditions
<h3>Third-party libraries</h3>
This plugin includes QRCode.js by davidshimjs to render QR codes locally in the browser.
Library: QRCode.js
Source: https://github.com/davidshimjs/qrcodejs
License: MIT
The QRCode.js license is included in <code>qrcode-license.txt</code>.

Checkify

Replace CAPTCHA with privacy-first human verification from Checkify.

greyfu

Greyfu Login Captcha adds a secure verification step to your WordPress login form, helping block automated login attempts and brute-force attacks.
Lite Version (Free): 
* Simple math-based captcha 
* Multisite compatible 
* Lightweight and fast 
* No personal data stored or transmitted 
* Works without any external service
Pro-Ready Features (Optional Upgrade): 
* Infrastructure prepared for reCAPTCHA v2 integration 
* Infrastructure prepared for hCaptcha integration 
* API key fields included
The free version is fully functional on its own and does not require any external captcha service.
<h3>Third Party Services</h3>
This plugin optionally connects to external captcha services when the Pro features are enabled:
Google reCAPTCHA (Optional) 
When reCAPTCHA is enabled in Pro settings, the plugin sends verification requests to Google’s reCAPTCHA service. 
– Service: https://www.google.com/recaptcha/ 
– Privacy Policy: https://policies.google.com/privacy 
– Terms of Service: https://policies.google.com/terms 
– Data sent: User’s IP address and reCAPTCHA response token 
– When: Only during login form submission when reCAPTCHA is enabled
hCaptcha (Optional) 
When hCaptcha is enabled in Pro settings, the plugin sends verification requests to hCaptcha service. 
– Service: https://www.hcaptcha.com/ 
– Privacy Policy: https://www.hcaptcha.com/privacy 
– Terms of Service: https://www.hcaptcha.com/terms 
– Data sent: User’s IP address and hCaptcha response token 
– When: Only during login form submission when hCaptcha is enabled
The free/lite version uses a built-in math captcha that does not connect to any external service.
<h3>Support / Contact</h3>
For issues or questions, please contact us: 
Email: hello@greyfu.com 
Website: https://greyfu.com

Greyfu Login Captcha

A lightweight captcha that protects your WordPress login page from automated bot attacks using a simple math challenge.

Checkify vs Greyfu Login Captcha