Wikipedia has over 55 million articles written by volunteers

As of 2024, the English Wikipedia alone contains over 6.7 million articles, with the entire project spanning 55 million articles in 327 languages. It is written and maintained almost entirely by volunteers — approximately 300,000 active contributors in any given month — and hosted by the Wikimedia Foundation, a non-profit that runs on donations. Studies comparing Wikipedia's accuracy to Encyclopaedia Britannica found comparable error rates for science articles. Wikipedia is one of the most-visited websites on the internet, yet operates with fewer than 700 staff — smaller than most medium-sized companies.

Source: Giles, Internet encyclopaedias go head to head, Nature (2005)