Archive of Our Own (AO3) is a non-profit, non-commercial archive for transformative fanworks and a project of the Organization for Transformative Works. Created by and for fans, it welcomes works inspired by books, music, art, games, television, film, real people, and many other fandoms. The archive hosts fan-created writing and art, with browsing and search tools for exploring works, bookmarks, tags, people, collections, and fandoms across categories such as anime and manga, literature, comics, movies, music, theater, and video games.

Users with accounts can share their own fanworks, follow updates from favorite works, series, or creators, take part in challenges, and keep track of works they have visited or want to read later. New users can request an invitation through the automated queue. AO3 also provides community news, FAQs, tagging guidance, and information about its policies and support channels. The site states that it welcomes all fans and fanworks. The page provided is an AO3 mirror intended to help users in mainland China regain access; it is supported by advertising, and it warns visitors to avoid ads asking them to download software or send SMS verification.