Citizendium
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Screenshot  The Citizendium home page with default format (2018) | |
Website type | Online encyclopedia |
|---|---|
| Available in | English |
| Creator | Larry Sanger |
| Website | en |
| Commercial | No |
| Registration | Optional (Required to edit pages, via request of account) |
| Launched | 23 October 2006 (pilot) 25 March 2007 (public) |
| Current status | active |
Content license | CC BY-SA 3.0 or later |
logocaption. Replace with logo_caption.url. Replace with website.type. Replace with website_type.launch_date. Replace with launched.author. Replace with creator.Citizendium (/ˌsɪtɪˈzɛndiəm/ SIT-i-ZEN-dee-əm; "the citizens' compendium of everything") is an English-language wiki-based free online encyclopedia launched by Larry Sanger, co-founder of Nupedia and Wikipedia.
Sanger had worked as paid staff with Jimmy Wales to make Nupedia and Wikipedia, but left for financial reasons. He had been the editor-in-chief of Nupedia, which had an editorial review process similar to Citizendium's.
It was first announced in September 2006 as a fork of the English Wikipedia, but instead launched in March 2007 with an emphasis on original content. The project's aim was to improve the Wikipedia model by providing increased reliability. It planned to achieve this by requiring virtually all contributors to use their real names, by strictly moderating the project for unprofessional behavior, by providing "gentle expert oversight" of everyday contributors, and through "approved articles" that undergo a form of peer-review by topic experts with credentials.
Active contributors increased through the first quarter of 2008 and then declined; by 27 October 2011, the site had fewer than 100 active members. The last managing editor was Anthony Sebastian, until the office was vacated in 2016. As of 21 July 2023, it had 17,956 "live" and 6,322 "lemma" articles (lemmas are undeveloped articles that contain little more than a definition, similar to stub articles on Wikipedia). As of 8 September 2025, this had changed to 16,440 articles with an additional 3,744 lemma articles.