Block spam comments, defend against login attacks, strengthen site security. Anti-spam, brute-force protection & two-factor authentication built in.
Alternatives to WPMU Block Spam By Math
Plugins below are selected for functional relevance and current directory signals. Active-install counts do not affect this ranking.
Relevant replacements
WordPress plugins with similar use cases
Compatibility and update metadata provide context, not a quality guarantee. Review each plugin’s details for your site.
Apply a simple mathematical captcha to specific buttons by providing their CSS class or ID to prevent spamming.
Completely disables all backend comment submissions (wp-comments-post.php, REST API, XML-RPC) to stop ghost comment spam.
The most complete free WordPress anti-spam plugin. Protects Contact Form 7, comments, login, registration, REST API, and XML-RPC — all in one shield.
Stop Contact Form 7 spam with honeypot protection, automatic IP blocking, duplicate submission prevention, disposable email filtering, rate limiting, …
Invisible spam protection for comments and forms — no CAPTCHA, ever shown to visitors.
Stop Spammers Classicv2026.6
A simplified, restored, and preserved version of the original Stop Spammers plugin.
Dam Spamv1.1.8
Spam protection for WordPress registration, login, comments, and contact forms.
Modular dual-layer anti-spam protection for WordPress forms and comments with custom TLD and email filtering.
JRT CommentShieldv1.0.0
Smart and AI-powered anti-spam protection for WordPress comments. Blocks bots and spam automatically, with optional ChatGPT-based detection.