Hentaigana are variants of hiragana; these variants are rarely used in the present day. However, hentaigana were used for personal names until 1947, creating a need for a standardized coded character set of hentaigana for administrative uses such as the basic resident register. There is also a demand for the ability to input and display hentaigana on computers for academic purposes such as in the historical study of the Japanese writing system and studies of the history of Japan. Using characters collected from letterpress printing and digital fonts, we defined a set of hentaigana to be used in the exchange of academic information. This set includes some variants that originate from the same Chinese character in order to accurately portray functional distinction in hentaigana use. We plan to submit a proposal to add this set along with the hentaigana used for administrative purposes to the ISO/IEC 10646 standard on October 2015.