U+FF11 "1" Fullwidth Digit One Unicode Character

Unicode Version 17.0

U+FF11 "1" Fullwidth Digit One is a typographic variant of the standard ASCII digit "1" that occupies the same visual width as a fullwidth CJK (Chinese, Japanese, and Korean) character, making it essential for achieving consistent vertical and horizontal alignment in East Asian text layouts where characters are typically monospaced and square-shaped. Its primary use is in environments where proportional spacing would break the visual grid, such as in Japanese, Chinese, or Korean documents, forms, and digital interfaces that require numbers to match the width of adjacent ideographs. Unlike the halfwidth "1", this fullwidth version ensures that text blocks remain orderly and balanced, particularly when numbers appear alongside fullwidth punctuation or kanji.

General Properties

Code Point U+FF11
Version Added 1.1
Name Fullwidth Digit One
Block Halfwidth and Fullwidth Forms
General Category Decimal Number
Canonical Combining Class Not Reordered
Bidirectional Class European Number
Decomposition Type Wide
Decomposition Mapping "1" U+0031 Digit One

Encodings

HTML Decimal Encoding 1
HTML Hex Encoding 1
UTF-8 Encoding 0xEF 0xBC 0x91
UTF-16 Encoding 0xFF11
UTF-32 Encoding 0x0000FF11
C/C++/Java Escape \uff11

Unicode Properties

NFC Quick Check Yes
NFD Quick Check Yes
Numeric Type Decimal
Numeric Value 1
Line Break Ideographic
East Asian Width Fullwidth
Changes When NFKC Casefolded Yes
NFKC Casefold "1" U+0031 Digit One
NFKC Simple Casefold "1" U+0031 Digit One
Script Common
Script Extensions Common
Indic Syllabic Category Other
ID Continue Yes
XID Continue Yes
Hex Digit Yes
Vertical Orientation Upright
Grapheme Base Yes
Grapheme Cluster Break Other
Word Break Numeric
Sentence Break Numeric