3D objects-based CAPTCHA to get rid of spam in comments.
As of April 2026, Ironclad CAPTCHA WP plugin is a WordPress image plugin with 10 active installations and a 1/5 rating from 1 reviews. It has been downloaded 9.8K+ times in total. Requires WordPress 2.3.1+ and PHP false+. Available on WordPress.org since 2010. Last updated 14 years ago — may have compatibility concerns. Top alternative: Firelight Lightbox.
With this plugin you can easily install and use Ironclad CAPTCHA in your WordPress blog. 3D captcha renders several intersecting colored and rotated objects and asks user to count objects of some type. Humans can easily do it (much easier than read twisted text) and bots can’t do it at all and never will. Moreover, this captcha stops even spammers with human-based recognition of captchas, as Ironclad CAPTCHA has very unusual answer entering process. Just install the plugin, register and get API key on the official site (for free) and forget about spam forever.
Go to Settings section in WP control panel and then to Ironclad CAPTCHA sub-section. You should get API-key to for your blog/site to make Ironclad CAPTCHA appear on it. In order to do this you should register her…
| WordPress | 2.3.1+ requiredTested up to 3.3.2 |
| PHP | false+ required |
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