Hyōgaiji

Hyōgaiji (, translated to "characters from outside the table/chart"), also hyōgai kanji (表外漢字) and jōyōgai kanji (常用外漢字), are Japanese kanji outside the two major lists of Jōyō, which are taught in primary and secondary school, and Jinmeiyō, which are additional kanji that officially are allowed for use in personal names.

Because hyōgaiji is a catch-all category for "all unlisted kanji", there is no comprehensive list, nor is there a definitive count of the hyōgaiji. The highest level of the Kanji kentei (test of kanji aptitude) tests approximately 6,000 characters, of which 3,000 are hyōgaiji, while in principle any traditional Chinese character or newly coined variant may be used as hyōgaiji; the traditional dictionaries the Kangxi Dictionary and the 20th century Dai Kan-Wa jiten contain about 47,000 and 50,000 characters, respectively, of which over 40,000 would be classed as hyōgaiji or non-standard variants if used in Japanese.

While many jōyō-kanji are printed using simplified forms (shinjitai, in opposition to traditional forms), hyōgaiji are officially printed with traditional forms such as 臍, even if some simplified variants are officially recognized in print, such as 唖.

Jinmeiyō-kanji list (used for names) recognizes in most cases traditional form and simplified form — when it exists.

However, other unofficial simplified forms exist, known as extended shinjitai (拡張新字体, kakuchō shinjitai) – these come by applying the same simplification processes as in the development of shinjitai. The newspaper Asahi Shimbun developed its own simplified characters, known as Asahi characters, and they have their own Unicode code points. Some of these simplifications are part of the standard JIS X 0208 and later versions. Among extended shinjitai, only a few are de facto frequently used, including 填, 頬 (extended shinjitai for the jōyō-kanji 塡, 頰) or 涜, 掴 (extended shinjitai for the hyōgaiji 瀆, 摑).

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