U+1D539 "𝔹" Mathematical Double-Struck Capital B Unicode Character

U+1D539 "𝔹" Mathematical Double-Struck Capital B is a stylistic variant of the uppercase letter B, designed in a bold blackboard bold typeface that is commonly used in mathematics, logic, and computer science to denote special number sets or algebraic structures. Specifically, this character often represents the set of binary numbers, Boolean algebra, or the Boolean domain, echoing the convention in which double struck letters like ℕ, ℤ, and ℝ symbolize fundamental number systems. It belongs to the Mathematical Alphanumeric Symbols block, which was added to the Unicode Standard to provide distinct codepoints for mathematical notation, ensuring consistent rendering across different platforms and fonts.

General Properties

Code Point	U+1D539
Version Added	3.1
Name	Mathematical Double-Struck Capital B
Block	Mathematical Alphanumeric Symbols
General Category	Uppercase Letter
Canonical Combining Class	Not Reordered
Bidirectional Class	Left To Right
Decomposition Type	Font
Decomposition Mapping	"B" U+0042 Latin Capital Letter B

Encodings

HTML Decimal Encoding	𝔹
HTML Hex Encoding	𝔹
UTF-8 Encoding	0xF0 0x9D 0x94 0xB9
UTF-16 Encoding	0xD835 0xDD39
UTF-32 Encoding	0x0001D539
C/C++/Java Escape	\ud835\udd39

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	"b" U+0062 Latin Small Letter B
NFKC Simple Casefold	"b" U+0062 Latin Small Letter B
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