In July 2012, about 96,000 digitized materials were added to the digital archives of the NDL. The newly-added materials include about 80,000 periodicals in natural science fields (available from July 19) and about 16,000 books published from 1868 to 1945 (available from July 26). They are accessible only on the premises of the NDL as copyrights have not yet been cleared.

As a result, the total number of the digitized materials provided inside the NDL is now over 2.2 million, including about 400,000 items available also on the Internet. Titles and table of contents of all the digitized materials are available in the National Diet Library Digitized Contents (Japanese).