defendium

Defendium-Checker is an innovative WordPress plugin designed to safeguard your website’s comment section from spam. By utilizing the robust Defendium API, this plugin meticulously scans incoming comments, effectively identifying and blocking spam. It’s a must-have tool for website owners seeking to maintain the integrity and cleanliness of their comment areas.

Defendium Checker

Defendium is a powerful spam checker plugin for WordPress, integrating with the Defendium API to scrutinize incoming comments for spam.

Silkalns

WP Chill

Cristian Raiber

A very useful plugin for everyone using WordPress. Adds reCaptcha security to the WordPress login form, register form and comment form. This plugin could help your blog get rid of a lot of spam comments or brute-force attacks.
Nothing gets passed it if the reCaptcha doesn’t validate.
A few notes about the plugin:
<ul>
<li>Supports audio or image captcha types</li>
<li>Can generate the reCaptcha image / audio type in a number of predefined languages</li>
<li>Adds reCaptcha protection to the WordPress login form</li>
<li>Adds reCaptcha protection to the WordPress register form</li>
<li>Adds reCaptcha protection to the WordPress comment form</li>
<li>Adds reCaptcha protection to the WordPress recover password form</li>
</ul>

Uber reCaptcha

This plugin adds the reCaptcha form to the WordPress login form, recover password form, register form and comment form.

Defendium Checker vs Uber reCaptcha