The line breaking rules in East Asian languages specify how to wrap East Asian Language text such as Chinese, Japanese, and Korean. Certain characters in those languages should not come at the end of a line, certain characters should not come at the start of a line, and some characters should never be split up across two lines. For example, periods and closing parentheses are not allowed to start a line. Many word processing and desktop publishing software products have built-in features to control line breaking rules in those languages. In the Japanese language, especially, the categories of line breaking rules and processing methods are determined by the Japanese Industrial Standard JIS X 4051, and it is called Kinsoku Shori (禁則処理).

Line breaking rules in Chinese text

Line breaking rules for Chinese language have been described in the reference of Office Open XML, Ecma standard. There are rules about certain characters that are not allowed to start or end a line, such as below.

Simplified Chinese

Traditional Chinese

Line breaking rules in Japanese text (Kinsoku Shori)

Line breaking rules of Japanese language are determined by JIS X 4051, Japanese Industrial Standard. It describes word wrap rules and processing rules for Japanese language documents. These rules are called Kinsoku Shori (禁則処理, literally prohibition rules processing).

Word wrap rules

Categories

Regarding prohibited characters, there are some conventions, known as "house rules", which are specific to individual publishers. The rules of some publishers contradict those of other publishers. For that reason, there are many conventions that are not supported by Western desktop publishing software tools, and that is the main cause of the growing demand of computerized phototypesetting systems.

Characters not permitted on the start of a line

Note: Kinsoku Shori does not apply to Japanese characters while one line contains not enough characters.

Characters not permitted at the end of a line

Do not split

Processing rules

Line breaking rules in Korean text

Line breaking rules for Korean language have been described in the reference of Office Open XML, Ecma standard. There are rules about certain characters that are not allowed to start or end a line, such as below.

Korean standards related to line breaking rules