Fullwidth & Halfwidth Text Converter (全角 / 半角)
Convert standard ASCII Latin text and Katakana into Unicode Fullwidth (U+FF01–U+FF5E / U+3000), or normalize Zenkaku text back into standard ASCII.
The Typographic Science of Zenkaku (全角) & Hankaku (半角) in East Asian Computing
In East Asian computing systems (Japanese, Chinese, and Korean — CJK), characters traditionally occupy an em square block, termed Zenkaku (全角 / Fullwidth). In contrast, Western Latin alphabets and punctuation in early monospace terminals occupied half an em square, termed Hankaku (半角 / Halfwidth).
To support legacy JIS X 0208 and Shift-JIS databases where Japanese forms, government postal forms, and banking inputs required uniform monospace alignment, Unicode standardized the Halfwidth and Fullwidth Forms block (U+FF00–U+FFEF). Each ASCII character from 0x21 (!) to 0x7E (~) maps directly to a fullwidth counterpart by adding the constant hex offset 0xFEE0 (e.g. ASCII ‘A’ U+0041 + 0xFEE0 = Fullwidth ‘Ａ’ U+FF21).
Key Applications of Fullwidth & Halfwidth Conversion
- •Japanese Web Form Normalization: Convert fullwidth telephone numbers (
０９０－１２３４－５６７８) and postal codes into clean standard ASCII. - •Vaporwave & Cyber Aesthetics: Create iconic wide-spaced 1980s retro text for Discord bios, TikTok headers, and gaming nicknames.
- •Katakana Normalization: Convert legacy halfwidth Katakana (
ｱｲｳｴｵ) into modern fullwidth Katakana (アイウエオ) for clean mobile rendering. - •East Asian Width (UAX #11) Conformance: 100% compliant with Unicode Standard Annex #11 width definitions.
Frequently Asked Questions (FAQs)
How does this tool convert between standard space and Ideographic Space?+
In fullwidth mode, regular ASCII space (U+0020) is automatically converted to the fullwidth Ideographic Space (U+3000), which occupies the exact width of a Kanji character.
Can this tool fix Japanese banking forms that require halfwidth Katakana?+
Yes! Select the "Halfwidth Katakana" mode to convert standard Japanese Katakana into the compact halfwidth characters required by Japanese online banking forms and ATM systems.
Will Fullwidth characters display properly on Discord and Instagram?+
Yes! Because Fullwidth characters are standard Unicode code points, they render natively on all smartphones, Discord, Instagram, and web browsers without needing any custom font installation.