Stack Exchange
A network of community-powered Q&A sites, including Stack Overflow, covering technology, a
Stack Exchange is a network of community question-and-answer sites covering technical and non-technical topics, including programming, mathematics, physics, aviation, electronics, and more. The network brings together topic-specific communities where users post questions, provide answers, and browse activity through live question feeds, user profiles, tags, answer counts, and site rankings.
The network includes Stack Overflow and other sites such as Super User, Ask Ubuntu, Server Fault, Unix & Linux, Mathematics, Electrical Engineering, and English Language & Usage. The company also offers Stack Internal, an enterprise knowledge platform that ingests and structures organizational data to provide verified knowledge to teams and AI agents, along with an API, Stack Data Licensing, and Stack Ads. Security vulnerability reporting is handled through a dedicated contact form, with a public Hall of Fame recognizing researchers who report issues directly.
Stack Exchange is intended for developers, technologists, and anyone seeking answers within a specific topic community. The community sites are publicly accessible, while Stack Internal is positioned for organizations seeking to manage internal knowledge for both human teams and AI systems.
12 alternatives to Stack Exchange
Ranked by how well each tool replaces Stack Exchange: shared features, audience, price and popularity.
- 69 out of 100 match—
Open source Q&A platform for PHP/MySQL
Covers 1 of 7 key features and is open source.
Free planOpen source60 out of 100 matchContact sales- 59 out of 100 matchFree
The home for technical questions and answers at Microsoft
Covers 0 of 7 key features.
Free plan58 out of 100 matchContact salesCommunity-run, open-source Q&A platform for building communities around peer-reviewed Q&A,
Covers 0 of 7 key features and is open source.
Open source56 out of 100 match—A forum for discussion about Bitcoin, its ecosystem, and related topics.
Covers 1 of 7 key features.
Free plan56 out of 100 matchFreeA Q&A platform software for teams, usable as a community forum or help center.
Covers 4 of 7 key features and is open source.
Open source54 out of 100 match—A comment system for blogs and websites that adds threading, profiles and moderation to a
Covers 3 of 7 key features.
Free plan54 out of 100 matchFreeJoomla! extensions for blogging, social networking, forums and comments
Covers 2 of 7 key features.
54 out of 100 matchContact salesFree and open source forum software for building online communities.
Covers 2 of 7 key features and is open source.
Free planOpen source53 out of 100 matchFreeModern forum software for community discussion
Covers 1 of 7 key features and is open source.
Free planOpen source52 out of 100 match$20/mo