Akismet checks your comments against the Akismet Web service to see if they look like spam or not.
#1 super security anti-spam captcha plugin for WordPress forms.
“…another popular solution to fight spam is Antispam Bee”—Matt Mullenweg, Q&A WordCamp Europe 2014
An exceptionally powerful WordPress anti-spam plugin that eliminates comment spam, trackback spam, contact form spam & registration spam.
No spam in comments. No captcha.
Contact Form 7 Honeypot - Adds honeypot anti-spam functionality to CF7 forms.
Integrates reCAPTCHA anti-spam methods with WordPress including comment and registration spam protection.
Todd Lahman's comment spam blocking plugin that blocks automated spam with zero false positives.
A lightweight plugin to protect email addresses from email-harvesting robots by encoding them into decimal and hexadecimal entities.
Bad Behavior prevents spammers from ever delivering their junk, and in many cases, from ever reading your site in the first place.
This plugin allows you to implement Google Captcha (reCAPTCHA) into web forms.
Powerful anti-spam plugin that eliminates blog comment spam. Finally, you can enjoy a spam-free WordPress blog! Includes contact form.
Spam protection plug-in, all-in-one, premium anti-spam. No comments spam & registrations spam, no email spam, protects any forms. Forget spam.
Aggressive anti-spam plugin that eliminates comment spam, trackback spam, contact form spam and registration spam. Protects against malicious attacks.
This plugin utilizes Google reCAPTCHA to help your blog stay clear of spams. BWP reCAPTCHA supports no CAPTCHA reCAPTCHA, Contact Form 7 and Akismet.
Gwolle Guestbook is the WordPress guestbook you've just been looking for. Beautiful and easy.
Encode mailto links, email addresses, phone numbers and any text to hide them from (spam)bots. Mailto links will be protected automatically.
Math Captcha is a 100% effective CAPTCHA for WordPress that integrates into login, registration, comments, Contact Form 7 and bbPress.
Zero Spam makes blocking spam comments a cinch. Install, activate and enjoy a spam-free site. Supports Gravity Forms, Ninja Forms, BuddyPress & mo
To protect your Blog from automated spambots, this plugin adds invisible formfields to your comment form.
No more SPAM by spiders scanning you site for email adresses. With CryptX you can hide all your email adresses, with and without a mailto-link, by con
The plugin adds a No CAPTCHA reCAPTCHA tag in Contact Form 7, which can be used to include a No CAPTCHA reCAPTCHA anti-spam field.
A clean, secure, plug-&-play contact form for WordPress.
Sabre is an acronym for Simple Anti Bot Registration Engine. It's a set of counter measures against spam registration on your blog.
Protect email addresses and mailto links from spambots and spamming. Easy to use without configuration.
Contact form with captcha plugin allows you to use a Google reCAPTCHA contact form on your blog. It requires PHP 5.0 or later.
An extremely powerful antispam plugin that blocks spam-bots without annoying captcha images.
Several types of captcha to protect your site in one easy to use plugin.
Kills spam dead in it's tracks. Be gone evil demon spam!