Kasuga

Tiny Comment Spam Blocker is a lightweight yet powerful plugin designed to protect your WordPress comments from spam. It employs five different techniques to detect and block unwanted comments:
<ol>
<li>Nonce Verification – Ensures that the comment form submission is genuine.</li>
<li>Submission Time Check – Blocks comments submitted too quickly to prevent bots.</li>
<li>Honeypot Field – Hidden field that traps automated spam bots.</li>
<li>User Agent Validation – Detects suspicious User-Agent strings and blocks them.</li>
<li>Forbidden Word Filtering – Blocks submissions containing words or phrases from a configurable list within the comment body, email address, or IP address.</li>
<li>JavaScript-Based Human Interaction Detection – Sets a verification token when mouse movement, scrolling, or touch interaction is detected.</li>
<li>(Option) Block Non-Japanese Comments – Blocks comments that do not contain Japanese characters (Hiragana, Katakana, or Han/Kanji), primarily targeting machine-translated or foreign spam.</li>
</ol>
These filters are applied in order: if a comment passes the first check, it proceeds to the second, and so on, until all checks are applied or the comment is blocked.
Additional features:
<ul>
<li>Option to log detected spam in a local log file (up to 1.0 MB).</li>
<li>Optional email notifications when spam is detected.</li>
<li>Easy settings page in the WordPress admin panel.</li>
</ul>
<h3>Settings</h3>
The plugin provides the following settings in the WordPress admin panel:
<ul>
<li>Enable Spam Protection – Toggle the spam protection on or off. When disabled, all anti-spam checks are skipped.</li>
<li>Save Spam Detection Log – Enable or disable logging of detected spam. Logs are saved in a local file up to 1.0 MB within the WordPress uploads directory.</li>
<li>Notification Email Address – Enter an email address to receive notifications when spam is detected. Leave blank to disable email notifications.</li>
<li>Minimum Submission Time (seconds) – Set the minimum allowed time between loading the comment form and submitting a comment. Comments submitted faster than this threshold are considered spam.</li>
<li>Forbidden Words List – Enter one forbidden word, phrase, or IP address per line. Submissions containing these entries in the comment body, email address, or IP address will be blocked. Case is insensitive.
<ul>
<li>Example: 
viagra 
online pharmacy 
spam@email.com 
164.138.205.72</li>
</ul>
</li>
<li>Block No Japanese Comments – If enabled, this becomes the final check: Comments that contain Japanese characters (Hiragana, Katakana, or Kanji) will be automatically accepted after passing other security checks. Comments without Japanese characters will be blocked.</li>
</ul>
<h3>Arbitrary Section</h3>
This plugin is designed to be lightweight and fast, ensuring minimal impact on site performance while providing robust protection against comment spam.

Tiny Comment Spam Blocker

A simple and lightweight yet rock-solid plugin that blocks comment spam using multiple automatic detection methods.

Julian Lang

Send Denial – a spam sentinel
This plugin will enable honeypot and other anti-spam techniques (in future versions) to protect your business and mailbox from automated script spammers. In “basic” honeypot mode there will be zero impact on your users. they won’t see a captcha or puzzle to solve, they can just use your websites forms. Plug and play
This plugin will be compliant with GDPR guidelines as it won’t call external apis or databases at all. In future versions there might be a local database table (in your database) where failed submissions (from bots) will be stored so you will have total control over the data.
currently supported (protected) plugins include:
<ol>
<li>Caldera Forms</li>
<li>WPForms Lite</li>
<li>CF7 (Contact Form 7)</li>
<li>Ninja Forms (including ajax submissions)</li>
<li>Formidable</li>
<li>WooCommerce (registration, checkout, login)</li>
<li>Elementor Forms (Pro)</li>
<li>MC4WP</li>
<li>Jetform Builder</li>
<li>Ultimate Member (Registration Form)</li>
<li>FormCraft Premium</li>
</ol>
planned support for the near future:
<ol>
<li>bbPress</li>
<li>Divi Forms</li>
<li>Fluentform</li>
<li>HTML Form</li>
<li>Gravity Forms</li>
<li>BuddyPress</li>
<li>Easy Digital Downloads Checkout</li>
<li>Toolset Forms</li>
</ol>
This plugin will support as many popular plugins as possible for free. There is no intent to sell “premium” anti spam protection in the future. You can help to support costly formbuilders or other paid plugins by donating a little amout to help fund the licenses for the development environment.

Send Denial

Anti-Spam protection for the most popular and widly used formbuilders and plugins. GDPR compliant.

Tiny Comment Spam Blocker vs Send Denial