U+339C "㎜" Square Mm Unicode Character

U+339C "㎜" Square Mm is a precomposed CJK compatibility ideograph that represents the square millimeter unit of area measurement, commonly used in technical and scientific contexts. It was included in Unicode primarily for compatibility with older East Asian character encoding standards, such as those used in Japanese industrial and typographic systems, where such squared unit symbols are frequently employed in technical documentation and specifications. This character occupies a single code point and is distinct from sequences of individual characters like "mm" or "mm²", as it is designed to display as a single, compact glyph for precision in specialized text environments.

General Properties

Code Point	U+339C
Version Added	1.1
Name	Square Mm
Unicode 1.0 Name	Squared Mm
Block	CJK Compatibility
General Category	Other Symbol
Canonical Combining Class	Not Reordered
Bidirectional Class	Left To Right
Decomposition Type	Square
Decomposition Mapping	"m" U+006D Latin Small Letter M "m" U+006D Latin Small Letter M

Encodings

HTML Decimal Encoding	㎜
HTML Hex Encoding	㎜
UTF-8 Encoding	0xE3 0x8E 0x9C
UTF-16 Encoding	0x339C
UTF-32 Encoding	0x0000339C
C/C++/Java Escape	\u339c

Unicode Properties

NFC Quick Check	Yes
NFD Quick Check	Yes
Numeric Type	None
Numeric Value	NaN
Line Break	Ideographic
East Asian Width	Wide
Changes When NFKC Casefolded	Yes
NFKC Casefold	"m" U+006D Latin Small Letter M "m" U+006D Latin Small Letter M
NFKC Simple Casefold	"m" U+006D Latin Small Letter M "m" U+006D Latin Small Letter M
Script	Common
Script Extensions	Common
Indic Syllabic Category	Other
Vertical Orientation	Upright
Grapheme Base	Yes
Grapheme Cluster Break	Other
Word Break	Other
Sentence Break	Other