AO3 is unique from other archives for several reasons. First, AO3 is built on supporting a mission of maximum inclusiveness of fanwork content. This means we want to preserve fannish content of all types—even if it is objectionable, abhorrent, bigoted, disgusting, or otherwise offensive to many people. This includes allowing fannish content that includes explicit themes such as rape, underage sexual content, graphic violence, or other mature content unless it violates the AO3 Terms of Service in some other way. You can read more about this in the AO3 Content Policy.

Second, AO3 is a 501(c)(3) non-profit. It is fully donor-funded and will never run advertisements. Accounts are free and will always be free. If you’re accessing AO3 through a browser or app that is charging you for access to AO3 or running ads, please contact us. This is a violation of our Terms of Service.

In addition to the above, AO3 is run on open-source archiving software that is available for use by anyone to customize and deploy as their own archive. Part of the OTW’s mission and goals is to support the development of other fanwork archives and we encourage others to use the otwarchive repository as a base to build other archives.