Zenkaku and hankaku
Japanese, Chinese and Korean text uses full-width (zenkaku, 全角) characters that occupy a square cell, matching the width of kanji and kana. Latin letters and digits also exist in full-width forms, Ａｂｃ１２３, and katakana exists in older half-width (hankaku, 半角) forms, ｶﾀｶﾅ, from early computer systems.
Mixing them causes real problems: forms reject full-width digits in phone numbers, searches miss “ＡＢＣ” when looking for “ABC”, and half-width katakana looks out of place in modern text.
What the converter does
- To half-width: full-width letters, digits, punctuation and the ideographic space become ASCII; full-width katakana becomes half-width katakana, with voiced sounds split into a base and a mark (ガ → ｶﾞ).
- To full-width: ASCII becomes full-width, and half-width katakana becomes full-width (combining ｶﾞ into a single ガ and ﾊﾟ into パ, which simple character-by-character converters get wrong).
Hiragana and kanji have no width variants and are left unchanged. To convert between hiragana and katakana, use the Hiragana ↔ Katakana Converter.
Worked example
Here is what the Full-width / Half-width Converter returns for its built-in example. Settings used: Convert to: Half-width; Include katakana: on. Click Try an example in the tool above to load it, then change it as you like.
Ｔｅｘｔｋｉｌｎ ２０２５！ ｶﾀｶﾅ ﾃﾞｰﾀTextkiln 2025! ｶﾀｶﾅ ﾃﾞｰﾀQuestions
How do I convert full-width numbers to normal numbers?
Choose “Half-width”. Full-width digits ０-９ become 0-9, along with letters and punctuation.
Does it handle dakuten (ﾞ)?
Yes. Half-width katakana with voicing marks is combined into the correct full-width character, and split again when converting back.
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