Top Alternatives to Plone

WordPress is an open source content management solution based on PHP maintained by Automattic which is also being offered as hosted solution.

Drupal is an open source platform for building websites.

Joomla is a free and open-source content management system (CMS) for publishing web content.

ImpressPages is an open-source PHP framework with built-in content editor.

concrete5 is an open-source content management system (CMS) for publishing content on the World Wide Web and intranets.

Tiki Wiki CMS Groupware or simply Tiki, originally known as TikiWiki, is a free and open source Wiki-based content management system and online office suite written primarily in PHP.

MODX (MODx) is a free, open source content management system and web application framework for publishing content on the world wide web and intranets. MODX is licensed under the GPL, is written in the PHP programming language, and supports MySQL and Microsoft SQL Server as the database.

Squarespace is a SaaS-based content management system-integrated website builder, blogging platform, hosting service and domain name registrar.

SilverStripe is a free and open-source Content Management System (CMS) and framework for setting up and maintaining websites and web applications.

Confluence is a team collaboration software. Written in Java and mainly used in corporate environments.

Web Start Today is a premium Do-It-Yourself (DIY) website builder.

CMS Made Simple (CMSMS) is a free, open source (GPL) content management system (CMS) to provide developers, programmers and site owners a web-based development and administration area.

Portofino is a web application framework for Java and Groovy developers. Its purpose is to help developers create outstanding enterprise applications.

Novius OS is a content management system (CMS) open source.

Sitefinity is a modern ASP.NET Web CMS, delivering intuitive web content management for business professionals, robust CMS development environment.

Symphony CMS is a XSLT-powered open source content management system.

Website X5 is a software that allows you to create autonomously websites, blogs and E-commerce.

Craft CMS is a content management system for developers, designers, and web professionals that blends flexibility, power, and ease of use for clients.

blogstrap.py is a simple Blog using web.py and bootstrap3.

Umbraco is an open source content management system (CMS) platform.