An extremely powerful antispam plugin that blocks spam-bots without annoying captcha images.
WPBruiser (formerly GoodBye Captcha) is an anti-spam and security plugin based on algorithms that identify spam bots without any annoying and hard to read captcha images.
WPBruiser completely eliminates spam-bot signups, spam comments, even brute force attacks, the second you install it on your WordPress website. It is completely invisible to the end-user - no need to ever fill out a Captcha or other "human-detection" field ever again - and it just works!
Unlike other anti-spam plugins, which detect spam comments and signups after the fact and move them to your spam folder, which you then have to delete - using up not only your website's resources, but your time as well, WPBruiser prevents the bots from leaving spam in the first place. The result is that your site is not only spam free, it's faster and more secure.
In addition, WPBruiser is completely self-contained and does not need to connect to any outside service. Your logins remain yours, 100%.
WPBruiser fights Brute Force attacks and eliminates spam-bots on comments, signup pages as well as login and password reset pages. At the click of a button, you can decide which forms to protect.
Step 1: Install it
Install this plugin by navigating Plugins -> Add New within your Admin dashboard, then searching for ' WPBruiser {no- Captcha anti-Spam} ', then click Install, then activate.
Alternatively you can head over here, download the plugin and then upload and extract it to your WordPress plugins folder.
Step 2: Use it
Use the plugin as shown in the below screenshots:
Reference
Read more here.