Wikipedia

Wikipedia articles are read more than 16 billion times every month

Nearly 300,000 volunteers worldwide help write, edit, and fact-check articles on the site in real-time, striving to ensure content is authored from a neutral point of view. All pages are freely accessible and must include citations to reliable, published sources.

On average, about five edits are made on Wikipedia every second

As of 2024, the site is 90 times larger than the 120-volume Encyclopedia Britannica, but its automation tools can often catch and revert inaccurate edits within 60 seconds. Its low-bandwidth, adless pages have allowed it to handle millions of site visits daily, even during times of high internet traffic.

Wikipedia openly displays edit history and editorial disputes to assess trustworthiness

Unlike a journal article, which may be reviewed by up to three people before publication, popular Wikipedia pages may be reviewed thousands of times by editors, potentially enhancing their reliability. Less reviewed articles still require reliable third-party sources and remain subject to verification by bots and administrators who can undo edits.

In late 2007, Wikipedia became the world's largest general encyclopedia

The record had been held for approximately six centuries by the Yongle Encyclopedia, which was commissioned by the Yongle Emperor of the Ming dynasty in 1403 to preserve information from ancient and imperial China. The text comprised 22,937 manuscript rolls in 11,095 volumes.

Research suggests articles on Wikipedia are about as reliable as 'accurate' sources

Studies from Nature, The Guardian, the Journal of Clinical Oncology, and the Canadian Library Association, among others, did not identify significant errors, particularly in articles related to academic topics. The site is still considered an exploratory, tertiary source subject to systemic biases from its human editors, especially within controversial topics.

A 15-year bibliographic analysis identified systematic gender bias across Wikipedia

A 2024 study by the University of Barcelona found that 71.4% of all English biographies that appear on the front page are about men, and approximately one in five editors are women. Researchers suggest systemic imbalances in society further diminish women's contributions to the site by leaving them with less time to defend edits during editorial disputes.

As of January 2026, 500 new articles are added to the English Wikipedia daily

The largest Wikipedia language edition features over 7 million articles, followed by the Cebuano edition (over 6 million) and the German edition (over 3 million). The longest article is the "2025 in women's road cycling" page, and the most edited is the list of personnel from World Wrestling Entertainment.

Wikipedia arose from a failed, for-profit online encyclopedia

Nupedia was launched in 2000 by internet entrepreneur Jimmy Wales and internet project developer Lawrence Sanger, only publishing articles written by experts after a cumbersome seven-step review process. The two developed Wikipedia to allow the public to write articles for future review, but shifting to self-moderation contributed to Sanger's departure in 2002.

The software for wikis—user-editable websites—was launched in 1995

Computer programmer Ward Cunningham created the WikiWikiWeb online application based on an offline system that helped track how ideas moved through his company. The application enabled users to collaborate and edit website content through a web browser, as well as link pages without requiring a structured navigation scheme.

As of 2025, the Wikimedia Foundation funds 14 open-source, free knowledge projects

Since its founding in 2003, the nonprofit has provided financial, legal, and infrastructure support to Wikipedia and its sister projects (e.g., Wikinews), primarily by managing donations, which average $11, from readers. Additional funding comes from gifts exceeding $1,000, the Wikimedia Endowment, and providing Wikipedia content for commercial use.