arminschaeffer

<p>This plugin serves as spam-filter for your contact forms powered by machine learning.</p>
<p>It shows the following advantages over other spam prevention methods:</p>
<ul>
<li>It does not hinder your users, the spam detection runs totally in the background (in contrast to captchas or verification questionaries).</li>
<li>It does not send the form data to third parties for spam detection. The detection is executed on your server.</li>
</ul>
<h3>Supported Forms Plugins</h3>
<p>At the moment, the following form plugins are supported:</p>
<ul>
<li>Contact Form 7</li>
<li>Formidable</li>
</ul>
<h3>Supported Languages</h3>
<p>At the moment, only english spam mails can be detected.</p>
<p>Normally, only english spam messages should be filtered, but due to the increasing use of english vocabulary in other languages, sometimes messages with other languages could be filtered out too, please keep this in mind.</p>


Wp SpamAinator

This plugin serves as spam-filter for your contact forms powered by machine learning.

Automattic

Donncha O Caoimh (a11n)

<p>This plugin adds a stylesheet or image to your blog’s html source code. When a browser loads that stylesheet or image a cookie is dropped. If that user then leaves a comment the cookie is checked. If it doesn’t exist the comment is marked as spam.<br />
The plugin can also check how long it took a user to enter a comment. If it’s too fast it’s probably a spam bot. How fast can a legitimate user enter their name, email, web address and enter a well thought out comment?</p>
<p>For the adventurous, add these lines to your .htaccess and it will block spam attempts before they ever get to WordPress. Replace the Xs with the cookie that was set in your browser after viewing your blog. You can also find the cookie value by examining the page source code and looking for “css.php?k=XXXXXXXXXXXXXXXXXXX”. Make sure the lines go above the standard WordPress rules.</p>
<pre><code>    RewriteCond %{HTTP_COOKIE} !^.*XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.*$
    RewriteRule ^wp-comments-post.php - [F,L]
</code></pre>
<p>If you use WordPress MU, replace wp-comments-post.php above with wp-signup.php to block spam signups.</p>
<pre><code>    RewriteCond %{HTTP_COOKIE} !^.*XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.*$
    RewriteRule ^wp-signup.php - [F,L]
</code></pre>


Cookies for Comments

If you don't use any other spam filter plugins, then you can rely on this to stop spam comments for sure!

Must have, if you don't use any other spam filters!

I'd been getting a dozen spams a day on two of my sites. We installed "Stop Spam Comments" on one and "Cookies for Comments" on the other. Both worked perfectly. No more spam. Thanks!



very easy and no more spam!

Sets a cookie on a random URL that is then checked when a comment is posted. If the cookie is missing the comment is marked as spam.

Wp SpamAinator vs Cookies for Comments