Wikipedia is a free multilingual open-source wiki-based online encyclopedia edited and maintained by a community of volunteer editors, started on January 15th 2001 as an English-language encyclopedia. Non-English editions were soon created: the German and Catalan editions were created on circa 16 March, the French edition was created on 23 March, and the Swedish edition was created on 23 May. As of January 2025, Wikipedia articles have been created in editions, with currently active and closed. The Meta-Wiki language committee manages policies on creating new Wikimedia projects. To be eligible, a language must have a valid ISO 639 code, be "sufficiently unique", and have a "sufficient number of fluent users".

Variations in editions

Wikipedia projects vary in how they divide dialects and variants. For example, the English Wikipedia includes most modern varieties of English including American English and British English. Similarly, the Spanish Wikipedia includes both Peninsular Spanish and Latin American Spanish, and the Portuguese Wikipedia includes both European Portuguese and Brazilian Portuguese. In contrast, some languages have multiple Wikipedias. For example, Serbo-Croatian encompasses four Wikipedia editions, Serbo-Croatian and three different standardized varieties (Bosnian, Croatian, and Serbian). Additionally, some Wikipedia projects apply different approaches to orthography. For instance, the Chinese Wikipedia automatically transliterates between six standard forms: three using simplified Chinese characters (Mainland China, Malaysia, and Singapore) and three using traditional Chinese characters (Taiwan, Hong Kong, and Macau Cantonese). And rather than relying on transliteration, Belarusian has separate Wikipedia projects for the official Narkamaŭka and Taraškievica orthographies.

Wikipedia edition codes

Each Wikipedia project has a code, which is used as a subdomain of wikipedia.org. The codes mostly conform to ISO 639-1 two-letter codes or ISO 639-3 three-letter codes, with preference given to a two-letter code if available. For example, en stands for English in ISO 639-1, so the English Wikipedia is at en.wikipedia.org.

Wikipedia editions

Active editions

The table below lists the active language editions of Wikipedia roughly sorted by the number of articles (excluding redirects and non-article pages).

Inactive editions

The table below lists the inactive language editions of Wikipedia.

Special editions

The table below lists the special editions of Wikipedia. The Nostalgia Wikipedia is an archive of the English Wikipedia's initial display.