Mediawiki v Confluence
Ultimately, this comparison matrix will probably live on MediaWiki.org - because it's useful to the wider MediaWiki community. And, there will be a modified version that compares the QualityBox distribution of MediaWiki hosted on https://demo.QualityBox.us/wiki/QualityBox_vs_Confluence
This article builds on the information at Wikipedia which is rather superficial but does allow you to dive into each product page. There is also the 'WikiMatrix' site that provides a more in-depth analysis and comparison of wikis (eg. BlueSpice vs MediaWiki vs Confluence.) But, that site is often incorrect, or at best stale.
Comparing MediaWiki to Confluence
In comparing MediaWiki to Confluence, we're also looking at what other vendors or analysts say about their comparisons. BlueSpice, a MediaWiki distribution which is specifically aimed at the enterprise market, is built by the German company Hallo Welt!. They offer an in-depth point-by-point analysis of the MediaWiki platform compared with Confluence (and give you the spreadsheet to see the details: 275 metrics in 18 categories!).
A simplistic conclusion when considering the origin of these products and their respective strengths would be that if your organization is a bunch of developers trying to push code out the door, then Confluence may be better because it does the essential "wiki" work; with integration into other tools needed in Software development. If you're an organization that has "Knowledge Workers" and you want to increase productivity, and revenue or decrease expenses around managing "company knowledge" then MediaWiki is probably the best solution. It excels at finding relevant information, collecting knowledge centrally, giving it context and structure, and curating its quality.
Are you a MediaWiki expert or consultant? Discuss this topic over at the QualityBox Discourse. Edits, corrections and contributions here are welcome!!
|License||GNU GPL||proprietary||Fully free software protects your investment because it's reversible and extensible from the bottom-up. It's never tied to the fate of a sole proprietor, and not subject to vendor lock-in.|
|Integration||almost anything||mostly Atlassian products|| MediaWiki can be, and is, integrated with a wide variety of other systems. Most importantly for the Enterprise user, a whole open authentication framework allows MediaWiki to be integrated with just about any existing authentication system. Because MediaWiki is open source software, with rich internal and external APIs, you can see exactly how you should integrate new functionality, new systems, etc. In contrast, Confluence is a closed system that supports only what is built into the system. "If you attempt to use an unsupported or custom JDBC driver collaborative editing will fail. You must use a supported driver." 
Atlassian likes to brag about how integrated Confluence is with their other systems (BitBucket, JIRA, Bamboo, FishEye, Crucible, HipChat). While it's true that these might be integrated , these extra products come at extra cost. Integrating Confluence with any product that is not sold by Atlassian is a different question.
|Ease of Use|| With 32,795,351 registered users on Wikipedia alone , there is a good chance your staff and new hires have used MediaWiki before. With options to edit in WYSIWYG, wiki markup, and other advanced options, MediaWiki is just as accessible and easy to use for the Sales Manager as it is for the Engineering Intern. The mobile website and other desktop clients give many ways to search, view, and edit. Technical users might find it easy to use an IDE such as Emacs or Vim to edit text files without a browser. MediaWiki has interfaces to allow you to edit from a git repository , or from desktop clients like LibreOffice.
Confluence wiki no longer supports editing with wiki markup - a decision that takes away ease of use for advanced users.
|Search|| MediaWiki Search is powered by ElasticSearch - which is built on top of Lucene. Several members of Elastic Co engineering contributed improvements to Lucene in 2017 .
Confluence Search is powered by Lucene, but doesn't have the breadth of syntax options and power of ElasticSearch
|Intended Audience||Any size group, organization or website. Public or private access. Open network or private network. Full end-to-end encryption available.||Smaller teams in a private LAN. SSL termination must be done at the gateway or proxy.|| With low standard limits on page indexing, and database pool connections , you may have a difficult time making Confluence scale and perform in larger installations. On the other hand, MediaWiki can scale to just about any size given the proper resources. What's more, MediaWiki is capable of not just creating a knowledge resource, it can also be used for general purpose websites, catalogs, documentation etc.
Confluence is limited in making documentation since page titles must be unique across the whole space
If you want to use SSL, there are instructions for Confluence, but it's totally up to you, and not supported by Atlassian. MediaWiki distributions like QualityBox offer SSL encryption built-in to every site by default, using the LetsEncrypt Certificate Authority.
|Gartner Magic Quadrant||If someone tells you that Confluence is better because MediaWiki isn't in the Gartner MQ, this argument is a red herring. There is no way that MediaWiki would ever be listed by Gartner since they review (large) vendors. MediaWiki is produced by the Wikimedia Foundation (WMF), a non-profit foundation. They are not a software vendor. They'll never be listed by Gartner in any MQ unless Gartner changes their methodology.  Besides, Atlassian was named in the 2017 MQ for "Enterprise Agile Planning Tools" , not for Confluence, not for wikis, not for collaboration, not for knowledge management.|
|Cost|| MediaWiki software is Free Software (as defined by it's license). Vendors charge for added value such as hosting, support, training and service -- including customization for your specific needs.
You pay per the seat for a Confluence license. There is a free option for open-source projects. There is a reduced price option for non-profit organizations. With Confluence, you even pay for simple features (Title redirects!) that are included with MediaWiki. On top of the licensing and software costs, you would still have to budget any remaining dollars toward hosting, support, training and service. Some things are just not available at any price (e.g. customization).
|Professional Support|| MediaWiki has paid professional support provided by a long list of individual software developers as well as companies around the world 
Confluence has a variety of support options available through a single company (Atlassian in Australia) with full support starting at $35,000 
|Testimonials||MediaWiki Testimonials Confluence Testimonials|
Confluence has a WYSIWYG editor. And so does MediaWiki. Whereas the Confluence editor understands XHTML markup, the MediaWiki editor was built exclusively for the MediaWiki project and understands wiki markup, templates, parser calls, magic words and features of the MediaWiki system. These advanced features are things that advanced users generally prefer to type directly (faster), but Confluence took away the ability to use straight wiki markup. You now have no choice but to use the WYSIWYG editor in Confluence.
Both Confluence and MediaWiki have search powered by Lucene. However MediaWiki takes it one level higher. By using ElasticSearch, there is a lot more search capability built into MediaWiki. And new documents are indexed in near real-time.
- https://demo.qualitybox.us/ QualityBox
- https://en.demo.bluespice.com/ BlueSpice
- https://templates.atlassian.net/wiki/spaces/CW/overview Confluence
Let's see who uses MediaWiki
Just about every established open source software project has a wiki.
- Some like Open EMR even use MediaWiki to document how to document their code
- On their own installation of Confluence, there is an error displaying integrated content from JIRA at the bottom of the page.
- Compare Confluence Search Syntax with MediaWiki Search Syntax
- Synchrony, the collaboration engine does not support HTTPS, so the communication within the application/data center must be done over plain HTTP.
- In the latest release notes for v6.2, the default pool size for database connections is 15