BotShield CAPTCHA adds powerful yet simple CAPTCHA protection to your Contact Form 7 forms without requiring any third-party API keys or services. Keep your forms spam-free while maintaining complete user privacy.

Features

Multiple CAPTCHA Types: Arithmetic challenges and alphanumeric image CAPTCHAs
Three Difficulty Levels: Easy, Medium, and Hard options to balance security and usability
No API Keys Required: Fully self-hosted solution with no external dependencies
WCAG 2.1 Accessible: Screen reader support and keyboard navigation included
Mobile Responsive: Perfect display on all devices and screen sizes
Three Built-in Themes: Default, Minimal, and Modern styles
GDPR Compliant: No data collection or third-party transmission
Lightweight: Minimal performance impact on your site
Auto-Refresh Option: Optional automatic CAPTCHA regeneration
Translation Ready: Full internationalization support with RTL language support

CAPTCHA Types

Arithmetic CAPTCHA
Simple math problems that are easy for humans but difficult for bots.
* Easy: Addition/subtraction with numbers 1-10
* Medium: Addition/subtraction with numbers 1-20
* Hard: Addition, subtraction, and multiplication with numbers 1-50

Alphanumeric Image CAPTCHA
Distorted text images with case-sensitive characters.
* Easy: 4 character challenge
* Medium: 5 character challenge
* Hard: 7 character challenge

Perfect For

Contact forms
Registration forms
Quote request forms
Newsletter signups
Any form needing spam protection

Security & Privacy

Token-based validation with HMAC signatures
Time-based expiration (5 minutes)
No external API calls
No data collection or storage
GDPR compliant
Fully self-hosted on your server

Requirements

WordPress 5.0 or higher
Contact Form 7 plugin (must be active)
PHP 7.4 or higher
GD PHP extension for image CAPTCHAs

Privacy Policy

BotShield CAPTCHA does not:
* Collect any personal data
* Store user information
* Transmit data to external servers
* Use cookies or tracking
* Share information with third parties

All CAPTCHA processing happens locally on your WordPress server. The plugin is fully GDPR compliant.

Support & Documentation

Support Forum: https://wordpress.org/support/plugin/botshield-captcha/
Developer Website: https://www.rsabbir.com/

Contributing

Contributions are welcome! Contact the developer or visit the GitHub repository to contribute to this plugin’s development.

Credits

Developed by R. Sabbir (https://www.rsabbir.com/)
SVG icons included (no external icon dependencies)
Tested with Contact Form 7 5.8 and later

Technical Specifications

Server Requirements

WordPress 5.0 or higher
PHP 7.4 or higher
Contact Form 7 plugin (active)
GD PHP extension (for image CAPTCHAs)

Browser Support

Chrome (latest versions)
Firefox (latest versions)
Safari (latest versions)
Microsoft Edge (latest versions)
Mobile browsers (iOS Safari, Chrome Mobile)

Security Features

Token-based validation system
HMAC-SHA256 signature verification
Automatic token expiration (5 minutes)
XSS protection
CSRF token protection
No session storage required

Performance

Code: ~50KB total size
Assets: Minified and optimized
Loading: Conditional asset loading on relevant pages
HTTP Requests: Zero external requests
Caching: Compatible with all major WordPress cache plugins

Installation

Automatic Installation

Go to Plugins > Add New
Search for “BotShield CAPTCHA”
Click “Install Now”
Click “Activate”

Manual Installation

Download the plugin ZIP file
Go to Plugins > Add New > Upload Plugin
Select the downloaded ZIP file
Click “Install Now”
Click “Activate Plugin”

Quick Setup

Verify Contact Form 7 is installed and activated
Go to Contact Form 7 > BotShield CAPTCHA in your admin dashboard
Configure your preferred CAPTCHA settings
Edit your Contact Form 7 form
Add the shortcode: [captcha* captcha-answer]
Save your form and test it

Frequently Asked Questions

Do I need API keys?

No! BotShield CAPTCHA is completely self-hosted with no API keys, third-party services, or external data transmission required.

Is it compatible with caching plugins?

Yes! The plugin works seamlessly with WP Super Cache, W3 Total Cache, WP Rocket, and other major caching solutions.

Does it work on mobile devices?

Absolutely! The CAPTCHA is fully responsive and works perfectly on all devices including smartphones and tablets.

Is it accessible for people with disabilities?

Yes! The plugin includes proper ARIA labels, keyboard navigation, and screen reader compatibility following WCAG 2.1 guidelines.

Can I customize the appearance?

Yes! Choose from three built-in themes (Default, Minimal, Modern) or add custom CSS for further customization.

What are the available CAPTCHA types?

Two types are available: Arithmetic (math problems) and Alphanumeric (image-based text). Each has Easy, Medium, and Hard difficulty levels.

Does it comply with GDPR?

Yes! The plugin doesn’t collect, store, or transmit any personal data. All processing happens locally on your server.

Can I use multiple CAPTCHAs per page?

Yes! Each Contact Form 7 form can have its own independent CAPTCHA configuration.

How do I specify the CAPTCHA type per form?

Use this shortcode syntax: [captcha* captcha-answer type:alphanumeric] or [captcha* captcha-answer type:arithmetic]

Can I make CAPTCHA optional?

Yes! Remove the asterisk from the shortcode: [captcha captcha-answer] (optional instead of required)

Does it affect site performance?

No! The plugin is lightweight and only loads assets on pages containing Contact Form 7. Minimal performance impact.

What if the GD extension isn’t available?

The image CAPTCHA requires GD. If unavailable, use the arithmetic CAPTCHA type instead. Most hosts have GD enabled by default.

How long are CAPTCHAs valid?

Generated CAPTCHAs are valid for 5 minutes. Users must refresh to get a new challenge after expiration.

Can I exclude logged-in users?

This feature is planned for a future release. Currently, all users must complete the CAPTCHA.

What are the browser requirements?

The plugin works with all modern browsers: Chrome, Firefox, Safari, Edge, and mobile browsers (iOS Safari, Chrome Mobile).

Review feed

No reviews available

Screenshots

Contact Form 7 tag generator interface for easy CAPTCHA shortcode creation
Contact Form 7 tag generator CAPTCHA settings with type and difficulty options
Arithmetic CAPTCHA displaying a math challenge on the contact form
Alphanumeric image CAPTCHA showing distorted text characters for security
Admin settings page with intuitive controls for configuring all CAPTCHA options

Changelog

1.0.0 – January 15, 2025

Initial plugin release
Arithmetic CAPTCHA with math problems
Alphanumeric image CAPTCHA with distorted text
Three difficulty levels (Easy, Medium, Hard)
Three visual themes (Default, Minimal, Modern)
Auto-refresh functionality
WCAG 2.1 accessibility compliance
Mobile responsive design
Contact Form 7 tag generator
Comprehensive admin settings
Translation ready with RTL support
Token-based HMAC security
5-minute token expiration
No external dependencies

Back to plugins