U+1D43C "𝐼" Mathematical Italic Capital I Unicode Character

U+1D43C "𝐼" Mathematical Italic Capital I is a typographic glyph used primarily in mathematical and scientific notation to represent a variable, such as the imaginary unit in complex numbers or an index in summation, while being visually distinct from the ordinary italic "I" used in prose. This character belongs to the Mathematical Alphanumeric Symbols block and is designed specifically to ensure that its italic styling remains independent of the surrounding text's font, allowing it to function as a semantic placeholder in equations. Its inclusion in Unicode supports the precise typesetting of academic papers, textbooks, and digital documents where clear differentiation between text and mathematical expressions is essential.

General Properties

Code Point	U+1D43C
Version Added	3.1
Name	Mathematical Italic Capital I
Block	Mathematical Alphanumeric Symbols
General Category	Uppercase Letter
Canonical Combining Class	Not Reordered
Bidirectional Class	Left To Right
Decomposition Type	Font
Decomposition Mapping	"I" U+0049 Latin Capital Letter I

Encodings

HTML Decimal Encoding	𝐼
HTML Hex Encoding	𝐼
UTF-8 Encoding	0xF0 0x9D 0x90 0xBC
UTF-16 Encoding	0xD835 0xDC3C
UTF-32 Encoding	0x0001D43C
C/C++/Java Escape	\ud835\udc3c

Unicode Properties

NFC Quick Check	Yes
NFD Quick Check	Yes
Numeric Type	None
Numeric Value	NaN
Line Break	Alphabetic
Uppercase	Yes
Cased	Yes
Changes When NFKC Casefolded	Yes
NFKC Casefold	"i" U+0069 Latin Small Letter I
NFKC Simple Casefold	"i" U+0069 Latin Small Letter I
Script	Common
Script Extensions	Common
Indic Syllabic Category	Other
ID Start	Yes
XID Start	Yes
ID Continue	Yes
XID Continue	Yes
Alphabetic	Yes
Math	Yes
Other Math	Yes
Vertical Orientation	Rotated
Grapheme Base	Yes
Grapheme Cluster Break	Other
Word Break	Alphabetic letter
Sentence Break	Upper