*All* sites that are not actual Q/A sites are not listed.

<!-- Editor: Remove this notice ONLY when you think it's complete. -->

- [SE Chat](https://chat.stackexchange.com)
- [SE Data Explorer](https://data.stackexchange.com)
- [SE Development Test site](https://dev.stackexchange.com)
- A few redirector sites
  - [Ask Ubuntu](https://ubuntu.stackexchange.com)
  - [MathOverflow](https://mathoverflow.stackexchange.com)

Strictly speaking, Area 51 is not *in* the list, but it's easily known and accessible (it's in the top-left dropdown menu of all sites, though).

### Sub-domains of StackOverflow.com:

- [Stack Overflow Blog](https://blog.stackoverflow.com) - This isn't really a sub-domain of stackexchange.com, but since SO is a part of the SEN, let it be here. And it even has an [**Alternative**](https://stackoverflow.blog). Why two...
- [Stack Overflow "Facebook" tag](http://facebook.stackoverflow.com) - Redirects to SO with tag `facebook`)
- [Stack Overflow Jobs](https://jobs.stackoverflow.com) - Redirects to SO Talent
- [RADS](https://rads.stackoverflow.com) - Used to be a dedicated redirection site. Closed now (redirects to SO)
- [SO Development site](https://dev.stackoverflow.com) - Not a test site

### Other *primary* domains that the Stack Exchange company owns:

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- [Stack Snippet](http://example.com "http://stacksnippet.com") - Host site for code snippets in Stack Exchange
- [Stack Snippet**s**](http://example.com "http://stacksnippets.com") - Jeff Atwood may have smashed a giant S on this domain. Makes no difference from the above one

  *Shadow Wizard* said those two domains are fraud. Link is temporarily suspended until comfirmation.
-->

- [Stack Promos](https://stackpromos.com)
- [SO Business](https://www.stackoverflowbusiness.com)