[1][2][3][4] The Zhonghua Zihai consists of two parts; the first section consists of characters covered in earlier dictionaries, such as the Shuowen Jiezi, Yupian, Guangyun, Jiyun, Kangxi Dictionary and Zhonghua Da Zidian, which covers just under 50,000 individual characters.
[5] The second portion of the Zhonghua Zihai contains characters missed by previous dictionaries, as a result of manual error or due to lack of knowledge of such characters.
One of the authors, Hu Mingyang, wrote in the preface of the Zhonghua Zihai stating that the problem regarding Chinese characters is that there is an exceedingly large number of them,[1] which makes compilation very difficult, and a complete dictionary practically impossible due to the large number of variant characters and those that are unknown.
In Japan, the 2003 edition of the Dai Kan-Wa jiten has some 51,109 characters, while the Han-Han Dae Sajeon completed in South Korea in 2008 contains 53,667 Chinese characters (the project having lasted 30 years, at a cost of 31,000,000,000 KRW or US$25 million[4][8][9]).
The Dictionary of Chinese Variant Form (Chinese: 異體字字典; pinyin: yìtǐzì zìdiǎn) compiled by the Taiwan (ROC) Ministry of Education in 2004 contains 106,230 individual characters,[1][10] many being variants.