U+FF71 "ア" Halfwidth Katakana Letter A Unicode Character

Unicode Version 17.0

U+FF71 "ア" Halfwidth Katakana Letter A is a typographic variant of the fullwidth katakana character ア, designed to occupy a single character cell width rather than the standard double width used in traditional Japanese text. This halfwidth form was originally developed for use in legacy computer systems and early digital environments, such as shift-JIS encoding, where space efficiency was a priority, often appearing in older terminal displays, teletext, or certain ASCII-influenced interfaces. While the fullwidth version remains standard in modern Japanese writing, the halfwidth ア is still supported in Unicode for compatibility with historical data and specific applications requiring narrower character spacing. Its visual appearance is identical in shape to the fullwidth ア, representing the vowel sound "a" in the katakana syllabary, but its narrower glyph helps maintain alignment in monospaced contexts or compact layouts.

General Properties

Code Point U+FF71
Version Added 1.1
Name Halfwidth Katakana Letter A
Block Halfwidth and Fullwidth Forms
General Category Other Letter
Canonical Combining Class Not Reordered
Bidirectional Class Left To Right
Decomposition Type Narrow
Decomposition Mapping "ア" U+30A2 Katakana Letter A

Encodings

HTML Decimal Encoding ア
HTML Hex Encoding ア
UTF-8 Encoding 0xEF 0xBD 0xB1
UTF-16 Encoding 0xFF71
UTF-32 Encoding 0x0000FF71
C/C++/Java Escape \uff71

Unicode Properties

NFC Quick Check Yes
NFD Quick Check Yes
Numeric Type None
Numeric Value NaN
Line Break Ideographic
East Asian Width Halfwidth
Changes When NFKC Casefolded Yes
NFKC Casefold "ア" U+30A2 Katakana Letter A
NFKC Simple Casefold "ア" U+30A2 Katakana Letter A
Script Katakana
Script Extensions Katakana
Indic Syllabic Category Other
ID Start Yes
XID Start Yes
ID Continue Yes
XID Continue Yes
Alphabetic Yes
Vertical Orientation Rotated
Grapheme Base Yes
Grapheme Cluster Break Other
Word Break Katakana
Sentence Break OLetter