The Linzer Sammlung, or Linz Collection, includes works stolen by the Nazis between 1939 and 1945 in Germany and German-occupied countries.
Hitler collected art systematically, "like beetles" gathered by an insect specialist, Berlin historian Christian Löhr, who helped build the data bank, told news agency DDP.
The former postcard painter turned Nazi dictator had envisioned building a museum for the massive collection of works after the war in his childhood home of Linz, Austria.
His private collection was to be displayed on the first floor of the unrealized museum, and the archive includes documents on floor plans for their exhibition. The data bank comprising 4731 artworks was a joint project between the museum and Germany's Federal Office for Central Services and Unresolved Property Issues (BADV). It includes images of paintings, sculptures, porcelain and furniture.
The BADV, responsible for the some 1,700 unclaimed pieces that still remain in state custody, hopes that the newly publicized information will spur new research to help return the works to their rightful owners.