Spamming has always been a big headache for bloggers. Today the problem is so severe that disabling comments completely seems to be the only fool-proof solution. However, for most bloggers this isn’t a viable option. Your blog can not become successful unless you promote discussion and allow users to leave their feedback on the posts you have published. Fortunately there are many WordPress anti-spam plugins available on the internet that can help you solve this problem.

Listed below are the 10 most effective WordPress anti-spam plugins in the WordPress plugin repository:

1. Akismet

This is indubitably the best tool against the ever-growing spam problem. It comes preinstalled with WordPress so all you have to do is activate it and enter your API key. This powerful plugin goes through every comment that is posted and sends the suspicious ones to the spam section. If the same or a similar comment has been marked as spam by other blog owners on their blogs, it automatically gets caught giving you the peace of mind you deserve.

Akismet has two versions, a free one and a paid one. Personal blogs can use the API and Akismet services for free while business and commercial sites need to pay in order to take full advantage of this brilliant system. The reason for this is that commercial sites tend to get a lot more traffic than personal blogs and in turn use more Akismet resources. If you have a personal site or a small blog, the free version should be more than sufficient for your needs.

2. WP-reCAPTCHA

Captchas have been an effective way to prevent spam since the early days of internet. reCAPTCHA is a project that was started by programmers at Carnegie Mellon University and later on acquired by Google. As opposed to traditional captcha systems, this system is almost impossible to crack by automated bots. Also the answers given by users are used to effectively digitize books. WP-reCAPTCHA plugin brings the power of this awesome system to WordPress. You can read more about it on the official website of the project.

3. Spam Free WordPress

This is another great option for banishing hackbots and spambots. It works with a wide variety of form plugins including Contact Form 7, Gravity forms and all the built-in WordPress forms. It is also a great option if your website is powered by the famous ecommerce plugin WooCommerce and you want to protect it from spam.

4. Growmap Anti Spambot Plugin

This tiny yet effective plugin can solve your spam problem simply by adding a client side generated checkbox to your comment form. A comment can not be submitted unless this box is checked. Since bots can’t execute javascript, they can’t add comments. The technique is extremely simple but it works in 99% of the cases. A huge advantage of this plugin is that it is extremely user-friendly as checking a box is much faster and easier than entering a long, difficult to read captcha code.

5. Bad Behavior

In addition to preventing spammers from posting spam to your blog, this plugin goes one step further and prevents them from visiting your blog. This way, your site loads much faster and logs are always clear. This plugin can be used with other spam protection systems in order to ensure that your blog is totally safe. The main reason behind its effectiveness is that instead of focusing on content like all the other antispam plugins out there, it analyzes the delivery method and the software being used by the spammer. This plugin is trusted by some very important organizations like SourceForge, GNOME, the U.S. Department of Education.

6. AVH First Defense against Spam

This is a very comprehensive anti-spam solution. It gives you the ability to check each visitor’s IP at Project Honey Pot, a local blacklist or the local IP cache. This way, spam can be caught before it reaches your blog. The visitor trying to post a comment is also checked at stopforumsspam.com before they can be allowed to post a comment. It has many other features as well. You can change the status of a particular feature from the included control panel. Despite of all these great features AVH First Defense against Spam is a relatively light-weight plugin. It was developed with speed and efficiency in mind.

7. WP-Hashcash

This plugin takes care of malicious bots on the internet that are used to spread spam on blogs. It does this by flagging a comment as spam if the visitor is unable to provide proof that they accessed the blog using a web browsers. This anti-spam plugin is also effective against pingback and trackback spam.

8. Peter’s Custom Anti-Spam

This plugin displays a captcha below your site’s comment form to prevent bots from using it. In order to make the plugin user-friendly, the author have used simple fonts in the captcha image which makes it susceptible to attacks. If your first priority is providing a pleasant user-experience then Peter’s Custom Anti-Spam is the way to go but if you want every spam comment to get caught then you should choose WP-reCaptcha instead.

9. BC Spam Block

This works similarly to the Hashcash plugin in that it is able to tell whether the user arriving at a page is a human or a bot. This is done with the help of JavaScript. Users who have javascript enabled can submit comments as usual however other users are required to enter a code into the comment area in order to verify that they are actual human visitors. As you can imagine, this can seem a bit counter-intuitive to some people. Trackback and pingback spam is also handled.

10. Defensio Anti-spam

This is an advanced spam filtering plugin for WordPress which learns and adapts based on the behavior of your users. The plugin can also be used to detect malicious content, categorize URLs and perform other security related tasks.

These are the best WordPress anti-spam plugins available on the internet. If you want to save your website’s resources and maintain your search engine ranking then you should start using at least one of these plugin right away.