AcFun (simplified Chinese: AcFun弹幕视频网; traditional Chinese: AcFun彈幕視頻網; pinyin: AcFun dàn mù shì pín wǎng), known as AC for short, is a Chinese video sharing website. AcFun is an abbreviation of "Anime, Comic and Fun". It is the first video sharing website which comments are overlaid on videos. The website is initially orientated as an ACGN(Animation, Comic, Game and Novel) community and is an influential video sharing website for its audience. AC Musume and TD Musume are the representative icons of AcFun.
The website allows users to upload, view and share videos. The users are able to comment in the comment section or directly put an overlaid comment onto the videos, resulting in more interaction and communication while watching videos.
In 2007, AcFun was created on June as an ACG themed video sharing site based on Sina Video.
In 2008, the site launched with a Niconico-style player.
In 2009, the site added Drama and Movies as new categories. People can create an account and upload videos.
In 13 February on 2010 they held their first Spring Festival Gala.
On 9 May 2010 the number of articles and videos submitted reached 100,000.
In 2011, AcFun had over 200,000 submitted articles and videos. The website changed its domain from acfun.cn to acfun.tv. It was awarded "Specialty Website of 2010" by Guangzhou-based New Weekly Magazine.
In 2014 the submission of articles and videos reached 1,000,000.
On 31 December 2014, AcFun did a live broadcast of Kōhaku Uta Gassen.
On March 2015, they moved their headquarters to Beijing.
On 6 June 2015, AcFun did a live broadcast of the show AKB48 anniversary year.
On 6 August 2015 AcFun received US$50 million series A funding from Youku Tudou Inc. at a reportedly valuation of US$200 million.
On 10 October AcFun registered a second-level domain "acfun.tudou.com".
On 14 January 2016 AcFun has completed a US$60 million funding round led by Softbank China Venture Capital.
On February 2, 2018, the website as well as Android and iOS apps were offline as the server shut down by its domain registrar Alibaba Cloud due to failure to renew the domain name. Possible financial constraints within AcFun may be related to the shutdown. The official Weibo account of AcFun confirmed the shutdown implicitly but no official statement regarding it has been made. The website and apps access has been restored as of February 12, ten days after the shutdown.