U+21D5 "⇕" Up down Double Arrow Unicode Character

Unicode Version 17.0

U+21D5 "⇕" Up down Double Arrow is a typographic symbol that represents bidirectional movement or opposition in both vertical directions simultaneously, formed by two parallel horizontal lines with arrowheads pointing upward and downward. It is commonly used in mathematics, logic, and technical diagrams to denote a double-headed vertical relationship, such as logical equivalence when oriented vertically, or to indicate that a value or entity can move or apply both upward and downward. In computing and user interface design, this arrow may also signify a toggle or a bidirectional scroll or zoom function along the vertical axis, distinguished from its single-line counterpart by its double stroke, which suggests a stronger or more formal connection.

General Properties

Code Point U+21D5
Version Added 1.1
Name Up down Double Arrow
Block Arrows
General Category Other Symbol
Canonical Combining Class Not Reordered
Bidirectional Class Other Neutral

Encodings

HTML Decimal Encoding ⇕
HTML Hex Encoding ⇕
UTF-8 Encoding 0xE2 0x87 0x95
UTF-16 Encoding 0x21D5
UTF-32 Encoding 0x000021D5
C/C++/Java Escape \u21d5

Unicode Properties

NFC Quick Check Yes
NFD Quick Check Yes
NFKC Quick Check Yes
NFKD Quick Check Yes
Numeric Type None
Numeric Value NaN
Line Break Alphabetic
Script Common
Script Extensions Common
Indic Syllabic Category Other
Pattern Syntax Yes
Math Yes
Other Math Yes
Vertical Orientation Rotated
Grapheme Base Yes
Grapheme Cluster Break Other
Word Break Other
Sentence Break Other