When comparing Disqus vs Discourse, the Slant community recommends Disqus for most people. In the question“What are the best comments systems for a blog?” Disqus is ranked 1st while Discourse is ranked 2nd. The most important reason people chose Disqus is:
Can be easily included into any website using the iframe form.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Can be easily integrated in any website via iframes
Can be easily included into any website using the iframe form.
Pro Seamless design
Seamless design that doesn't require users to leave the page to access features such as profiles.
Pro Wide adoption
There's a large pre-existing user community. Many people already know how to use this comment system.
Pro Works with static sites
Disqus can be used with a static site so it's possible to keep the benefits of a static blog and still have dynamic comments.
Pro Not connected with the Evil Facebook ecosystem.
Pro Clean, minimalist interface & design
The Disqus design is minimalist and is broken down into three tabs - discussion, community and My Disqus.
The discussion interface provides the usual elements, but with unique features like visual indicators of live actions, such as new replies and even when another user is typing. It's possible to sort discussion by new, old and best.
The community tab is designed to help connect commenters together to form a network that keeps them coming back. It is also a great source of traffic from external sites.
My Disqus helps users quickly keep track of activities in their network as well as manage notifications.
Pro Community features
Community features such as Top Commenters, Top Discussions and the ability to form networks around your own commenters
Pro Has a built-in immune system from trolls, spammers and bad actors
Discourse has a simple user trust system that makes moderating the forum a lot easier. Users gain more permissions as they gain more trust, which limits the amount of damage spammers and trolls can do. Discourse co-founder Jeff Atwood also founded StackExchange, which is the gold standard for gamification/moderation systems so you can also expect Discourse to get better and better at moderation.
Pro 100% free and fully open source
Discourse is powered by Ruby on Rails, Ember.js, PostgreSQL and Redis. The code is licensed under GPL and available on GitHub.
Pro Modern & polished UI/UX with lots of great smaller features
The best feature is its design: discourse is designed to aid in the creation of high quality online conversations. Flat discussions with well implemented quoting systems, expandable/collapsible replies, infinite scroll, clean UI and many more features come together to form a highly polished forum experience that makes legacy forums show their age.
Pro Helpful community
Discourse has a comprehensive forum culture support hub at meta.discourse.org.
Pro Hosted and self-hosted solutions
You can host it yourself in a $5 cloud server or on any Linux server you already have. And if you don't want to deal with this, you can use the hosting platform from the development team.
Pro Live preview while editing the post
The post editor has a synchronized side-by-side preview of the Markdown rendering of the post.
Pro User selectable themes
Users can choose between the themes made avaliable on their instances, and even use different themes on different devices (mobile vs desktop, for example).
Pro Export your posts
Pro Effective search
Pro Good to go out of the box yet infinitely tweakable
Discourse has sane, safe out of the box defaults, but a million dials and knobs to tweak.
Pro Easy one-click upgrade
Discourse can upgrade itself with one click in the admin panel. Not the same can be said about MyBB, or most other forums.
Pro Advanced JavaScript app
Runs in modern browsers and works identically on desktop and tablet and smartphone without the need for a native app.
Pro Discussions can be organized in categories and tagged
Discussions can be tagged with an arbitrary number of tags, separately from categories. Categories are hierarchical and don't scale; tags do.
Pro Official Akismet Anti-Spam Plugin
Official Akismet plugin vets posts by new users to make sure they don’t look spammy before they hit your site. Akismet key purchase required.
Pro Extensible via plugins
Pro Good on-boarding experience for new users
New users are greeted withe the disco bot which has an interactive experience to teach the basics of using Discourse.
Cons
Con Does not allow you to customize its style
Disqus uses !important
flags in its CSS to prevent you from being able to customize its style at all.
Con Closed-source
Con It may be old
The interface looks very dated.
Con Sponsored comments
Disqus puts ads in their embeds.
Con Tracking users
Mining and selling their data.
Con Complicated setup
Compared to standard PHP+MySQL apps, Discourse is more complicated - the app lives in a Docker container. However, a Docker image is available, which reduces the setup time to about 30 minutes.
Con Leaves out users with shared hosting
Discourse requires sudo, which is only available on a VPS.
Con Bad noscript support
When using a Discourse forum without scripts the experience is greatly reduced. It's really hard to use and is read-only, meaning that one can't comment or create threads without scripts.
Con It is more "Free to Try" than really free
Discourse is open source free software. The hosting is where the costs come in. Discourse.org hosting starts at $100/mo, but you can pay as little as $5/mo on Digital Ocean or other cloud hosts.
Con Extremely expensive hosting
Official discourse.org hosting starts at $100/mo and supports the team creating the software. It can also be hosted on a cloud service like Digital Ocean for $5/mo.