Fullwidth Latin Capital Letter I

Ｉ is the fullwidth form of the Latin capital I.

It has the same letter identity and pronunciation as I, but preserves a fullwidth East Asian layout distinction. In a mixed grid of Latin letters and East Asian text, it can occupy a full cell.

JIS C 6226-1978 is one documented Japanese encoding context for fullwidth forms: its 94×94 grid placed Latin letters alongside kana, symbols, and kanji. These forms served mixed-width text systems that needed full-cell Latin characters alongside older single-byte text. By 2024, repeated fullwidth capitals were also documented in vaporwave and lofi titles and comments as “aesthetic” lettering—a later visual convention, not the character's original purpose.

When should I use Ｉ?

Use it for a fullwidth layout, when a field asks for zenkaku, or for a deliberate fullwidth style. Ordinary English, code, identifiers, and search terms usually call for ASCII I. The two forms are distinct characters, though compatibility-aware software may normalize Ｉ to I.

The width distinction describes layout behavior; it does not dictate the exact drawn width. A font and layout engine determine how either character appears on screen.